Journal of Criminal Law and Criminology Volume 31 Article 12 Issue 4 November-December

Winter 1940 Human Studies: General Considerations of Hair Individualization and Its Forensic Importance Paul L. Kirk

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Recommended Citation Paul L. Kirk, Human Hair Studies: General Considerations of Hair Individualization and Its Forensic Importance, 31 Am. Inst. Crim. L. & Criminology 486 (1940-1941)

This Criminology is brought to you for free and open access by Northwestern University School of Law Scholarly Commons. It has been accepted for inclusion in Journal of Criminal Law and Criminology by an authorized editor of Northwestern University School of Law Scholarly Commons. HUMAN HAIR STUDIES* 1. General Considerations of Hair Individualization and Its Forensic Importance Paul L. Kirkt

Human hair unquestionably figures whether a suspected hair belongs to a as a clue or possible clue in a very con- particular person is rarely carried fur- siderable percentage of crimes, particu- ther than to observe its most obvious larly those of violence, but only slight- properties, such as its color and its ly less in crimes of stealth, since most length, points which are obviously of individuals have a greater or less tend- very limited value. This is even more ency to lose unconsciously and surprising when most criminal investi- at random. It is indeed strange that so gators are well aware of the possibili- tempting a type of evidence should ties of distinguishing the animal species have been so indifferently treated by of the hair, and spare no pains in en- criminal investigators. Some criminol- larging, sectioning, and otherwise in- ogists have expressed confidence in vestigating the hair from this stand- their ability to determine the source of point. This phase of hair study has un- a hair, but usually without benefit of doubtedly been inspired by such ex- adequate study and by methods that cellent investigations as those of Glais- are not generally known. The common ter (2), Hausman, (3) and others. attitude is well expressed by Sydney Some investigators (1, 4) go further Smith (1) who states, "If a definite and claim to determine age of human answer is required as to whether a cer- hair by such methods as measuring the tain sample of hair is that of a certain rate of solution of a hair root in caus- individual, the investigator is strongly tic potash. It would seem at least as advised to refuse to go further than to difficult to accurately determine the age state that the hairs are similar". With- as to determine the individuality of the out question, present knowledge justi- hair, if there is any analogy to other fies such a statement to a very consid- bodily structures such as friction erable -extent, but to accept this view ridges, or the physiogomy. fatalistically as the last word on the While thorough studies of the indi- subject is as strange as the attitude vidualization of human hair have not taken by many toward fingerprints in been reported, the total amount of hair the early days of development of that investigation which has been published important branch of criminological is very impressive. Without attempting knowledge. To the best of the author's to completely review the literature, information, the investigation as to some of the more recent and outstand-

* These studies were made with the aid of a Works Progress Administration. grant from the Research Board of the University t Associate Professor of Biochemistry, Uni- of California, and of clerical assistance from the versity of California. [ 486 ] HUMAN HAIR STUDIES ing contributions are here listed. Haus- tors which may be significant in deter- man (3) has contributed an extensive mining individuality. series of papers on this subject, chiefly Early results of these studies appear from the anthropological point of view. to point very definitely to the possibil- Trotter (5) has made valuable sys- ity of making such identifications with tematic studies on human hair and has a very considerable degree of proba- reviewed the classification of hair (6) bility. It has, for example, been cus- quite thoroughly, along with an .excel- tomary for some years to require all lent bibliography. Another recent study students of criminological science in of classification was made by Eddy (7). the author's laboratory to identify a Methods of examination of hair have single hair from one of twenty samples, been discussed by Roig (8), Harvey all of similar color and from individ- (9), Fiale (10), Bellamy (11) and uals of similar age. To the present, no others. General discussions of the for- such student who has completed the ensic importance of hair and its study routine examination has failed to re- are included in most books on crim- port the identification correctly. While inology and forensic medicine, includ- this falls far short of placing a hair on ing Smith and Glaister (12), Soderman a single member of the world's popu- lation, it must be remembered and O'Connell (13), Smith (1), Dan- (a) that twenty suspects in a single crime is forth (14) and other similar references. rather an exceptional number; (b) Older work which has often been that the eliminative value of a failure quoted but is frequently inaccurate and to identify the hair as that of any of occasionally misleading is that of Lam- the suspect's is great; (c) that time bert and Balthazard (15). imposes on students a restriction on Since it is a matter of common obser- the total number of hairs that can be vation that an individual's hair is usu- examined, and it is impossible as yet ally more or less distinct in appearance to say whether they. could equally well from that of other individuals, it ap- pick, e.g. from 100 standards; (d) that peared well worth investigating to as- in any random group of suspects there certain if there are differences which would be greater normal variations are sufficiently fundamental and of than are present in the selected group sufficient magnitude to lend a reason- of similar hairs used for this exercise; able probability to an identification of and (e) that the students in question a person from one or more of his hairs. have never before examined hairs and In this series of papers it is hoped to are in no sense experts in this exam- report studies of various observable ination. and measurable differences of hair in In addition to the question of locat- sufficient numbers that statistical anal- ing from which of a number of hair ysis may be employed to determine the samples a single hair has been taken, exact variations of each of these fac- a considerable number of criminal PAUL L. KIRK

cases involving human hair have been well. In order to make examinations investigated with results that are, to of hair, certain routine matters of say the least, gratifying. In one case, handling and preparation must be con- two fugitives from justice were located sidered. exclusively on the basis of a single hair If the bodily origin is definitely contained in the hat of one of them known it must naturally be recorded, which had been lost in flight. The iden- even to the extent of distinguishing be- tification in this case was later con- tween crown, nape and or firmed by fingerprints. In another case, temples of human head hair. Other hair believed to have come from the body hairs need not be considered here victim of an assault was located in the for they have not been studied to the lodgings of a suspect, while hair diag- extent of making individualization pos- nosed as that of the suspect was located sible as yet. Naturally it is necessary on the victim. The diagnosis was con- to be able to distinguish body hairs firmed by a plea of guilty. In another from head hairs, a matter which is case, the identification of the hair of a usually simple to the person who has suspect was confirmed by sufficient ad- had some experience in hair examina- ditional evidence of other types that a tion. It is as yet uncertain whether jury found the suspect guilty. In these hair from different portions of the head as in other cases, the individualization shows consistent differences which are of the hair has without exception been significant, but the distinction of areas confirmed when there were indepen- should be made until evidence is ob- dent means of obtaining confirmation. tained to settle the point. It would be imprudent to conclude The head hair is first examined with- that the procedure may for this reason out any cleaning or other treatment by be made infallible, but the results cer- placing it on a microscope slide, cover- tainly justify further studies so that as with a cover slip and examining it un- high a degree of probability as possible der magnification. At times there are may be attained in hair identification. particles of adherent matter which may At the very least, it is surely possible be significant. Ordinarily the debris is to develop the technique to the point merely a mixture of dandruff, oil, and of making it a valuable addition to common dust. After determining the criminological methods. importance of the debris, the hair is washed thoroughly in a mixture Technique of Examination of equal parts of ether and alcohol The total possible number of factors in a covered which might be studied in connection dish. This washing should be with human hair identification are very continued with agitation for about 15 large. Only those which have so far minutes, or even longer when prepar- proved to be of value will be briefly de- ing it for the measurement of such scribed here, though undoubtedly many properties as refractive index. In the more will ultimately prove useful as latter case it is sometimes necessary to HUMAN HAIR STUDIES

make a second washing with clean sol- times difficult to find sufficiently thin vent to ensure absolute removal of all cover slips to allow the objective to be grease. The hair is dried in the air, lowered into focus. In this case a sim- preferably on a clean filter paper, and ple expedient is to fasten the hair to then it may be cut into lengths of the slide by covering it with a piece of about one half inch for convenience in transparent Scotch tape (16). This mounting. Short hairs must be cut into type of mounting may for convenience still shorter pieces for it is necessary to be substituted for all dry mounts of make more than one mounting for a hair. It has the disadvantage that if complete examination. In measuring the hair is to be subsequently mounted some properties such as diameter, re- in another way it must be recleaned to fractive index and birefringence, it is remove any adhesive from the tape. desirable to make short sections not Air bubbles which are frequently more than 1 mm. in length. This is con- trapped are another source of difficulty. veniently done by mounting two As a general rule it is unnecessary to on a thin brass block, so that the make cross sections, in spite of the very edges are parellel and about 1 mm. great prevalence of this custom. In dis- apart. This simple device will cut any tinguishing species the cross section has number of short sections of equal a very definite value which is, how- length. ever, not so great even in this case as A portion of the hair is mounted dry it has been considered by some. In under a cover slip which is sealed to human hair studies, the only factors the slide with a little Kronig cement which are given by a cross section are (1 part beeswax melted with 4 parts the minimum and maximum diameters, resin), taking care not to allow the the appearance of the medullary canal cement to contact the hair. Another and the cross sectional pigment distri- portion is mounted in Canada balsam. bution. The first factor is readily de- Millimeter sections are laid aside for termined without sectioning (as will be special purposes, or else made as described later), and indeed, much needed. In case the amount of hair is more accurately, because of the tend- too small for simultaneous mountings ency of the hair to pull in the and without balsam, the dry mount sections, thereby giving an oblique cut may be examined and later mounted in rather than a normal 900 section. The balsam. In case of necessity, the bal- second factor is relatively insignificant sam mount may be cleaned in xylene in identification, and can also be seen and remounted dry. in the longitudinal view, though some- Occasionally hair is encountered with what less clearly, with transmitted such dense pigment that transmitted light. The third factor occasionally has light is inadequate for its examination. significance, chiefly in determining the In these cases the Ultropak illuminator relative central or peripheral distribu- is helpful. If the magnification must be tion of the pigment. This can be also great (e.g. 50x objective) it is some- seen in the balsam mount by focussing PAUL L. KIRK up and down and observing the shift not only impossible to say how many in the maximum density of the pig- of these are subject to investigation ment. Finally, the technique of cross but also how significant any of them sectioning is not one that can be done may ultimately be found. Those which ordinarily without considerable experi- have proved of value up to the present ence, and to a very considerable extent will be listed here and discussed. it destroys evidence. For these reasons it is considered preferable to save the Morphological Factors cross section for a final resort in case 1) Color. This factor is the most no decision can be reached without it. obvious one to the inexperienced indi- In the author's laboratory this has oc- vidual as well as to the expert. Its in- curred just once, and in that case more terpretation, however, must be made experience in the lateral examination with caution. Certainly when gross dif- would undoubtedly have settled the ferences are found in the color of two point. hairs, it is a fair assumption that they Necessary micoscropic observations did not have a common origin. This is may now be made on the mounted hairs particularly true when the actual color in any way desired. The use of magni- rather than the shade or hue is differ- fications greater than about 50 0x is ent. But experience shows that differ- generally useless. The increased thin- ent hairs from the same head will fre- ness of the field and the poorer quently have rather wide variations in resolution with higher powers more color, making necessary a careful scan- than offsets any advantage of greater ning of many hairs of the individual magnification. The single important furnishing the standard. This is espe- exception to this statement is the de- cially true with blond hairs. Only if tailed examination of the pigment gran- the color of the questioned hair falls ulation which must often be performed within the known range of the standard with oil immersion objectives. As in- is this factor significant. If it falls dicated above, the use of the Ultropak without, it is left to the investigator illuminator is sometimes highly advan- to be sure that his standard is really tageous, particularly for examination representative. Nevertheless, in a ma- of the cuticle layer, but also for deeper jority of cases the differences of color structure in many instances. For ex- may be legitimately used for prelim- ample, the medullary canal is very inary elimination. easily observed under this instrument. It would be highly desirable to estab- Study of pigment distribution is gen- lish an absolute color chart for hair erally made with transmitted light. (11) and in addition to make accurate studies of the characteristics of hair Characteristics for Study pigments in order that their chemical Almost an unlimited number of char- identity or difference might be deter- acteristics and sub-characteristics of mined as a check on the color alone. hair may be studied and at present it is 2) Diameter. Since human hair is HUMAN HAIR STUDIES nearly always oval in cross section eters throughout their hair while others rather than round, it is necessary that show great variation. One case studied the two extreme diameters be deter- showed a three-fold difference in both mined before any significance other minimum and maximum diameters be- than a gross idea of the hair coarseness tween his smallest and his largest may be attributed to the measurement. hairs. If sufficient hairs are available An accurate cross section undoubtedly for study, this variation itself should allows the simplest measurements of be significant, i.e., a person with uni- minimum and maximum diameters. form diameters could be distinguished Since it is so difficult to obtain such sec- from one of very non-uniform diam- tions, the technique employed in this eters. Many data will need to be col- laboratory is to use millimeter sections lected before any absolute significance which have been cut as previously de- may be ascribed to this factor. For the scribed. These are placed on a slide same reasons, the index of curvature, which has been slightly frosted by gently small diameter rubbing two slides together with a little large diameter is variable from hair to fine, moist carborundum powder be- hair and from point to point on the tween them. Such a short section will in same hair, though it is probably true nearly every case lie in its stable posi- that the average of a large number of tion, i.e., with the broad diameter par- measurements, and possibly the range allel to the surface of the slide. A cali- of variation, may be shown to be sig- brated ocular micrometer may then be nificant for individualization as well as used directly to obtain the maximum for racial characteristics. diameter, and a calibrated fine adjust- 3) Scale Count. By scale count is ment on the microscope will give the meant the number of scales intersecting minimum diameter. For the latter a line laid along the axis of the hair, measurement the instrument is first and of some known length. The usual focussed sharply on the frosting of the technique in the author's laboratory is slide, and the fine adjustment microm- to move the hair so that one line of eter is read; then it is focussed on the the cross hair in the microscope ocular very top of the hair section and read bisects the hair longitudinally while again. With care this method gives re- the calibration marks of the ocular mi- sults nearly as accurate as those read crometer are at right angles to the from the cross section but with much length of the hair. Each intersection of less effort, and avoids the important a scale edge which crosses the bisecting posibility that the section is not cut cross hair is counted, usually over the exactly across the hair. length of the ocular micrometer scale. The significance of diameter deter- For comparative purposes the same minations in individualization of hair micrometer and microscope are used does not appear from preliminary ob- with all the hairs in question so that no servation to be very great. Certain in- absolute calibration need be applied. For dividuals have relatively uniform diam- absolute data, the length of the mi- PAUL L. KIRK crometer scale is determined and the systematic fashion, but in spite of this, scale count corrected to that of some they may have considerable value in standard length (e.g., 0.2 mm., as used hair individualization. It is observed in this study). that many hairs have regular scale The significance of scale count means structure with little variation from part and ranges both appear to be very defi- to part. When this is the case, pre- nite. As eliminative factors each usu- liminary studies indicate that it is a ally serves to reduce the number of characteristic of the individual and possible hairs by about 3/4 or 4/5, pro- may be expected on all of his head vided enough counts are made so that hairs to a great degree. On the other the averages become reasonably sig- hand, when the scales are irregular in nificant. At least 25 counts are usually size (e.g., large interspersed with made before the average is taken, and small), in shape, or in contour lines, this average is only interpreted to serations, etc., that also will be found about +10%, though the average usu- quite generally over the range of hairs ally falls closer than this to the grand from that individual. Except for the average for the individual. More con- work of Eddy (8), little if any sys- cretely, if the average scale count is 24, tematic study has been made of these all hairs with averages below 22 and scale properties, but it seems a subject above 26 would be considered as defi- well worth investigating, even though nitely from another individual, and nothing more definite may be said than those between 22 and 23 and between that the experienced hair examiner will 25 and 26 would be considered as im- be able to use the scale picture to a probable, but subject to further com- very considerable degree in individual- parison. A final value for scale count izing hair. From a limited number of average and range should be based on hairs of different origin, it has been at least 100 counts, the averages being found possible in many cases to identify more closely interpretable. The statis- unknown hairs correctly on the basis tical significance and interpretation of of this property alone. these factors will follow in a subse- (5) Pigment Distribution. Of the quent publication. We can conclude various factors utilized in individuali- however, that scale count has a very zation of human head hairs, the distri- considerable value both in description bution and appearance of the pigment of hair and as an eliminative factor. granules in the cortex of the hair has 4) Scale Picture. By scale picture proved to be one of the best, if not the is meant the general characteristics of very best. Again, so many factors are the scales which are observable, such included under the term of pigment as the shape, regularity or irregularity distribution that it is difficult to discuss of sizes, and edges, and such other fea- or adequately separate them. First tures as may be observed microscop- might be considered pigment density ically. These characteristics are by far and density distribution. In general the the hardest to study or to discuss, in a pigment density is inversely propor- HUMAN HAIR STUDIES tional to the amount of light that may granules. Unquestionably the pigment be transmitted through the hair under granulation varies greatly between in- some standardized set of conditions. dividuals with respect to the general Where the density approaches a maxi- shape of the granules which are laid mum, there is almost no light trans- down. Normally the granule is defi- mitted as in certain very black hairs nitely elongated, so much so in some found most often in the negro race and cases as to appear as a thin streak. In to a lesser extent in races of Asiatic ori- other cases the granules approach a gin. A minimum density would be roughly oval shape with a much lesser found in very light blond or gray hair. degree of elongation, while still other The density distribution refers to the individuals show a definite alignment fact that in most cases the pigment of discrete granules, giving the appear- granules in human hair tend to cluster ance of great elongation. A study of close to the periphery of the hair, but this factor will show quite characteris- this tendency varies somewhat from tic differences between the hair of dif- person to person. It may be observed ferent people, particularly with respect in cross section most easily, but may to the coarser granules, and becoming also be studied by focussing up and more significant as the different sized down on a balsam mount of a section granules are considered. of the hair lying lengthwise of the slide. Pigment distribution, consisting as it Another sub-factor of importance is does of these various factors may be the distribution with respect to size of utilized to a very great extent in hair granules. Some persons show a relative individualization. Because of its com- uniformity of size which may range plex nature, however, it is a factor from so small as to be scarcely visible which must be very thoroughly studied under high power, up to granules which over a considerable period of time be- are very coarse. Most persons exhibit fore it will yield its maximum results. a greater or lesser lack of uniformity It is hoped that it may be broken down of granule sizes, so that in one hair we into its sub-factors for study and that may see all sizes of granules. However, reproducible means may be found for the relative proportion of coarse to fine evaluating each of the sub-factors. granules (based on some arbitrary size (6) Medullation. The presence or basis) will vary enormously between absence of medulla in head hair has individuals, but not greatly between little significance, nor does its appear- hairs from the same individual. This ance have much more. It is true thaf is a difficult factor to treat quantita- individuals vary considerably with re- tively though it is quite apparent to the spect to the total medullation shown experienced observer. by their hair, and to this extent the Another factor which is important factor becomes useful. Cases have been and even less susceptible to exact de- observed in which nearly every hair scription is the shape of the pigment showed medulla and most hairs had PAUL L. KIRK

virtually continuous medulla. The most defined. When two hairs of the same striking case in which this was found diameter are examined between crossed was with an elderly woman whose cor- Nicol prisms, it will be observed that tex was uniformly devoid of pigment. those from different sources frequently show different interference colors, Physical Factors while those from the same origin will Refractive Index. As will be shown generally be of the same color. Further in a later paper, refractive index of careful study of this property is ex- hair is a characteristic of very definite pected to produce results of very con- value, both for individualization and siderable significance in individualiza- for race and sex determination. The tion of human head hairs. range of refractive index is consistently Miscellaneous. Many additional phys- higher for female than for male hair, ical properties suggest themselves. and apparently for Asiatic races than Drawing analogies to the extensive for European races. Within the same work done with the mechanical proper- sex and racial type, the range is fairly ties of wool, such factors as tensile narrow, but broad enough to cover sev- strength may be of consequence. It eral times the probable error, and has been noted that permanently waved therefore, to serve for the elimination hair stretches very readily in compari- of at least 3/4 of all possibilities. As an son with untreated hair. This suggests individualization characteristic, it is the development of a method for study comparable in its eliminative and posi- of the stretch coefficient, a matter tive value to scale count. which is receiving preliminary investi- Birefringence. All hairs show the gation. Virtually nothing is now known characteristic of being more or less re- of the electrical properties of hair fractive, though with the exception of which may also prove to be of definite hairs used as textile fibers, little notice significance when they are studied. of this fact seems to have been recorded. Unlike a truly crystalline material, the Chemical Factors lack of morphological homogeneity in It seems virtually certain that the the hair makes quantitative study of hair will reflect differences in its chem- this property exceptionally difficult and ical environment during growth. Again it has not progressed to the point at making use of the analogy with wool which any final conclusions may be it is recognized that the cystine content drawn. Preliminary investigation ap- varies with the nutritional state of the pears to indicate that this factor, too, sheep. It is equally certain that some will have a definite eliminative and elements such as arsenic and probably some positive value for individualiza- silicon are selectively taken up in the tion when the means of studying it hair. Though there is little available have been sufficiently standardized and proof, it is obvious that hair color itself HUMAN HAIR STUDIES must to some extent depend on chem- tions that they produce in the other ical differences of the pigment, and it more basic factors listed for study. is equally logical to believe that at Permanent waving, for instance, alters least a part of the morphological differ- many morphological factors including ences in hair are based on correspond- diameter and scale count, and physical ig chemical differences. As previously properties such as birefringence and mentioned, the rate of solution of the tensile strength. Dyeing naturally al- hair bulb in caustic potash is widely ters hair color, but not pigment color, used for indicating sex of hair, and the while bleaching alters the latter as extensive work of Tadokoro (17) and well. others (18) indicates that sex has a very important effect on the chemical Various diseases affect the growth or makeup of epidermal structures, in- permanence of the hair. To what ex- cluding hair. The difference in hair tent such alterations as are produced distribution in the sexes, as well as by disease may be expected to alter other similar secondary sex character- the morphological, chemical or phys- istics may be largely a reflection of the ical properties has not been estab- difference in the basic chemical make- lished, but it is scarcely to be doubted up of the system exhibiting these prop- that there are such effects. While a erties. complete study of hair must take into All of these factors, and others, account all such factors as the above, clearly point to a large undeveloped their criminological importance is prob- field for investigation in the basic chem- ably not great except in instances in- istry and chemical differences of hair. volving a long lapse of time between So far as is known to the author, no time of collection of questioned hair chemical methods have been employed and of standard. thus far in hair individualization. The large number of morphological, physical and chemical factors which Other Factors may be studied in hair investigation, Many factors of an artificial, patho- and the preliminary indication from a logical or accidental nature may enter study of a few of these factors definitely in the individualization of human hair. points to the possibility that human Most common of these are self imposed head hair may be positively individ- treatments such as artificial waving and ualized and used in personal identifica- dyeing. While such treatments are usu- tion. Before such identification can be ally very obvious to the examiner and considered as definite, large numbers will have a greater or less significance of data must be collected and analysed in the individualization, the most im- statistically. portant result is probably the altera- (List of References on next page.) PAUL L. KIRK

REFERENCES 1. Smith, S., Forensic Medicine (1936) Lon- 8. Roig, J. D., "Technique for the Medico-legal don. Examination of Hairs," Ann. med. legale 2. Glaister, J., and Glaister, J. Jr., A Text- police sci. criminol., 12: 225 (1932). book of Medical Jurisprudence and Toxi- 9. Harvey, L., "The Examination of Hairs," cology (1931) Edinburgh. Police J., 11: 61 (1938). 3. Hausman, L., "The Relationships of the 10. Fiala, G. F., "Preparation of Hair for Microscopic Structural Characters of Hu- Cross-Section Examination," Amer. J. Phys. man Head Hair," Amer. J. Phys. Anthro- Anthropol., 14: 75 (1930). pol., 8: 173 (1925); "Structural Character- istics of the Hair of Mammals," Amer. 11. Bellamy, R., "Measuring Hair Color," Amer. Naturalist, 54: 496 (1920); "A Comparative J. Phys. Anthropol., 14: 75 (1930). Racial Study of the Structural Elements of 12. Smith, S., and Glaister, J., Recent Advances Human Head Hair," Amer. Naturalist, 59: in Forensic Medicine (1931) London. 529 (1925); "The Pigmentation of Human 13. S~derman, H., and O'Connell, J. J., Modern Head Hair," Amer. Naturalist, 61: 545 Criminal Investigation (1936) New York. (1927); "The Cortical Fusi of Mammalian Hair Shafts," Amer. Naturalist, 66: 461 14. Danforth, C. H., Hair with Special Refer- (1932). ence to (1925) Chicago. 4. May, L. S. Crime's Nemesis (1936) New 15. Lambert, M., and Balthazard, V., Le poil York. de l'homme et des animauvx (1910) Paris. 5. Trotter, M., "The Forms, Size and Color 16. Herzog, A., "A Simple Method for Partly of Head Hair in American Whites," Amer. Mounting Fibers for Microscopic Examina- J. Phys. Anthropol., 14: 433 (1930). tion," Melliand Textilber., 19: 405 (1938). 6. Trotter, M., "A Review of the Classifica- 17. Tadokoro, T., Sex Differences from the tions of Hair," Amer. J. Phys. Anthropol., Standpoint of Biochemistry. 24: 105 (1938). 18. Piepenborn, J., "Chemical Differences in 7. Eddy, M. W., "Hair Classification," Proc. Male and Female Hair," Z. ges. exptl. Pennsylvania Acad. Sci., 12: 19 (1938). Med., 76: 587 (1931).

[The second paper of this series (II. Scale Counts) will appear in the next issue of this Journal.]