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Ko. 3841, JUNE 12, 1943 NATURE 675 building to avoid noise and vibration from other were five valid species of Platyarthrus, four of these activities. Besides regular laboratory space, this in­ being restricted to the Mediterranean region, and only cludes a large 'dead' room for response measurements one, P. hojJmanse.ggi Brdt., being found throughout of microphones and loud speakers, two 'live' rooms Europe. In 1931 Archangeli described a new species or reverberation chambers for transmission and from the Canary Islands, and in 1934 Demianowicz absorption measurements and a small auditorium. reported two more from Bessarabia. The Connecticut The auditorium was built primarily for experi­ species was identified as Platyarthrus hofjmanseggi ments in auditorium acoustics and its construction Brdt. Its distribution is given as Upper Italy, Spain, follows the latest practice in acoustic treatment. To France, Switzerland, Holland, .Germany, Denmark, break up reflections, the side walls are splayed and Austria, Hungary, Russia and the British Isles. the rear wall is sloped away from the seats for the North Branford, Conn., is the first place in the same purpose. Panelling at the rear of the room, New " 7orld where a Platyarthrus has been found. and tha~ on ,,the adjacent side walls and ceiling, is In all probability it was accidentally introduced perforated and backed by absorbing material to re­ from Europe. duce reflected sound from. these areas. There are All the species of this genus are myrmecophilous, 363 _seats. · Each is upholstered to absorb about as but roost of the observations concerning them are much sound when not occupied as would a person, confined to the species in question. Although Was­ thus maintaining the same reverberation character­ roann considered P. hoffmanse.ggi to be pan-IJ'.l.yrmeco­ istics in the room whether it is empty or filled to philous, Prof. Brooks says that it has not been capacity. For the convenience of the audience, the recorded with other ants than those he lists. He s·eats are widely sep!l,rated in accord with European point,s out that the records from the Continent are practice. Although made quite reverberant for from Archangeli ; and for England from Donisthorpe, musical reproduction, the excellent acoustic charac­ and Webb and Sillem. He is indebted to Prof. Neal teristics of the listening room make it exceptionally A. Weber for the names of the ants with which it has satisfactory for speaking. There are no windows. been found in America. Decorative lights are mounted on the side walls. Prof. Brooks considers that the data indicate the Recessed lamps are di!!tributed uniformly over the existence of some factor or factors governing the ceiling and spotlights illuminate the platform and presence of this sowbug only in the nests of certain speaker. These groups of lights can be used sep­ species in any region. This is possibly the case ; arately or in combination and most .of them can also but I am inclined to think that if collectors had he dimmed. always recorded the presence of the crustacean when A technical library is an indispensable adjunct to they had seen it, or had specially looked for it, the a research laboratory, and provision has been made number both of localities and species of ants would at Murray Hill for this need by transferring about be considerably greater. eight thousand volumes from the main library at As Mr. Brooks is not a myrroecologist himself, he New York City. Reference books and technical can be excused for some errors in his list. of ants.· periodicals make up most of the collection, since other There. are no species called Myrmica ruja, or Formica books are always available on request from New flam. Also the genus Atta F. only occurs in Texas, York. The stacks are made of sheet steel with Mexico, Central and South America, and has cer­ adjustable metal shelves, slotted to .prevent the tainly never been recorded from Europe. Atta accumulation of dust, and the front edge of the lowest cephalotes L., not cephalotis, is recorded from the two shelves is tilted upward to aid in reading titles. basin of the Amazon, Columbia, Central America, Along two sides of the· room there is a row of small and Mexico. Furthermore, as Prof. Brooks says study carrells with chair, writing-table and shelves himself, he has used the generic nomenclature adopted for the convenience of tho~ who have long assign­ by the Committee of the Royal Entomological ments and who wish to have several reference books S.ociety of London, and thus has been 'let down' immediately at hand. This is a valuable feature, , about Acanthomyops. For example, A. Juliginosus because it provides privacy and avoids the confusion Latr. belongs to the subgenus Dendrolasius Ruzsky. and disturbance of a common study table. It could be called, accordin~ to whether one accepts The additional' facilities provided at the· Murray Lasius or Acanthomyops as the genus, either Lasiua Hill Laboratories are in great demand in the present (Dendrolasius) juliginosus Latr., or Acanthomyops war emergency, and are contributing effectively to­ (Dendrolasius) Juliginosus Latr., but never Lasius ward the solution of many problems posed by the (Acanthomyops) (see Donisthorpe, Ent. Record, 49, conflict. Practically the entire staff is now engaged 143; 1937). Also flavus F., and urr,bratus Nyl., in war work. belong to the subgenus Chtonolaaius Ruzsky. The variety of Formica fusca L. is glebaria Nyl., not gleboris. ,ve now come to Prof. Brooks' experimental work to endeavour to discover the factors involved in the A MYRMECOPHILOUS relationship between the woodlouse and its hosts. WOODLOUSE These are of a delicate, ingenious, and painstaking nature. They are intended to test the response to N the spring of 1938 Prof. G. E. Hutchinson found light (phototaxis), un9riented response (photoklino­ I a small white blind myrmecophilous sowbug in kinesis), response to atmospheric humidity gradient, ]S'orth Branford, Connecticut. The species was after­ and the reaction to a gradient of formic acid vapour, wards found in ants' nests in a small t.ract of country and are illustrated by diagrams, graphs, histograms, several miles in area round about the original localfty, etc. The results are briefly as follows. Platyarth.rus and within the Mti . ..Carmel region of Hamden, Conn., hoffmanse.ggi showed no direct response. to light some nine miles from North Branford. under the conditions used in the experiments. It Prof.. J. L. Brooks, in a recent paper (EcolQ(l.Y, 23, showed. a lower. klinokinesis in the light than in the No. 4, 427-37; 1942), points out that in 1921 there dark, .and the klinokinesis of this species was found © 1943 Nature Publishing Group 676 NATURE JUNE 12, 1943, VoL. 151 to be much greater than that of the non-myrmeco­ pioneer work now yielding results in the United philous woodlouse Oniscus asellus. It moved towards States on the electrolytic production of manganese the humidity end of a humidity gradient, as does from low-grade ores. also Oniscus asellus. It is attracted towards formic Turning to the sphere of electrodeposition, bright acid vapour, whereas Oniscus asellus avoided it. It plating, which was first introduced some years ago, was indifferent to acetic acid vapour, but that of has since made great strides. This is particularly propionic acid repulsed it. noticeable in the case of nickel and latterly also of In my observation nests I foWld that Platyarthrus .zinc. Electrogalvanizing has now to a large extent h<'jfmanseggi always sought the dark chambers of the superseded the old hot-dip process, while considerable nest, but this is probably because they are the progress is being made in the corresponding electro­ dampest, and also they are those usually inhabited tinning industry. Hard chromium plate is in wide by the ants themselves. demand throughout the engineering industry as a Prof. Brooks considers that the evidence strongly means of obtaining improved resist8'\ce to surface supports the supposition that Platyarthrus is chiefly wear and abrasion cf metals and alloys. Efforts found in the nests of those ants which possess an which continue to be made to find a non-toxic sub­ appreciable amount of formic acid. He says that stitute for plating baths of the cyanide type appear the question of the food of this species has never to be meeting with some success, more especially as been adequately answered. He quotes what I wrote regards the deposition of copper. Recent work on on this subject: "Lord Avebury suggested that it the deposition of aluminium from non-aqueous fed on spores of the lower plants, such as would be electrolytes has led to the development of a process found in ants' nests. These, however, would not be which is now being exploited on a semi-industrial present in plaster nests, and I believe that the food scale. Considerable advances have also been recorded of this species also, in part at least, consists of the in the deposition of alloys-a field which for certain 'boulettes de nettoyage' from the ant's infrabuccal engineering and other applications would appear to cavity''* ; but he points out that Platyarthus has offer possibilities. been kept in the laboratory for months away from Until only a very few years ago, electrolytic polish­ ant,s, and has even reproduced itself. He thinks it ing was almost W1known outside the laboratory, but is obvious that these creatures are not directly rapid progress has been made recently in the indus­ dependent on ants, but that the n ests of the latter trial development of this method of surface finishing. provide an environment in which they have a better In the electrothermal field the most noteworthy chance of surviving.

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