Nature [ October

NATURE [ OCTOBER. 2 7, 1910 and the foilowing extract from the Agricultural Gazette consideration. The attendance at the meetings of the of N ew South · Wales (August 2) is of interest:-" The section was very satisfactory, especially in the circum Chief Quarantine Officer for Plants has informed the stances, and the interest in the proceedings was fully main U oder-Secretary for Agriculture of a most extraordinary tained to the e nd; indeed, the concluding meeting was one method whereby an objectionable weed might be broad of the best of the series. casted throughout the State. It appears that, as an advertising medium, some printed paper, representative of Coral Snakes and Peacocks. a flyin g insect, has been sent to Austra li a, and the genius The popular lecture, which for several years has been who invented this particular style of advertisement, in an a f eature of the programme of the section, was given endeavour to make it more realistic or uncommon, had before a large audience by Dr. H. F. Gadow, F.R.S., a ttached to each specimen the burr or seed of the noxious who chose for his subject " Coral Snak es and Peacocks," wee d ' Burdock ' (Arctium Lappa). The authorities in and illustrated his remarks by a s eries of lantern-slides in W estern Australia had called the attention of the Director colour. He first described some of the physical features of Qua rantine to the use to which the burr of this noxious to which country his observa weed was being _put. It is needless to say that business of Mexico, during a visit were made. The red, black, firms s topped the issue of the advertisement under notire tions on cora l snakes (Elaps) and yellow ma rkings of these snakes have been said to be as soon as they knew there was a serious objection to j ts use. " of the nature of " warning coloration," but Dr. Gadow pointed out that, although the ma rkings a re conspicuous Burdock is a very troublesome weed, and it is clear in a d ish or other vessel, the that our colonial friends have to be on the alert if they when the sna kes are lying colours commingle, especially in the dusk, with the a re to prevent the introduction of new plants in the manner outlined. natura l surroundings of the animal, so that it becomes very inconspicuous. Coral snakes arc e ntirely nocturnal in habit; they lie in hiding during the day, so that the THE LANCASHIRE SEA-FISHERIES expla nation of their coloration as " warning " is un LABORATORY. wa rrantable. Many harmless snakes are coloured in a similar m anner to the coral snakes, e.g. among a large THE eighteenth report of the Lancashire Sea-Fisheries collection of Coronella from various places in Mexico Laboratory (for the year 1909) conta ins an account of examples of one species were found which seem to have work carried out at the University of Liverpool, at the " mimicked " s everal of the colour patterns e xhibited by sea-fish ha tchery at Piel, and at the Port Erin Bio speci es of Ela ps. But Dr. Gadow pointed out that the logical Station. Mr. J a mes Johnstone describes five specimens of Elaps and Coronella found in the same species of internal parasites of fi shes from the Irish locality do not exhibit the same c olour pattern. Dr. Sea, the · three genera discussed being Lebouria, Gadow's c onclusion, stated briefl y, w as that the resem Prosthecobothrium, and Echeneibothrium. The same bla nces in colour pattern between C oronell a and Elaps a uthor reports on the measurements of some 55,000 plaice are instances of pseudo-mimicry. In the second part of from the district, curves representing the frequency of fish his address Dr. Gadow traced the gra dua l transition from a t each unit of length for the most important fishing a compa ratively simple feather with light a nd dark bands grounds being given. The average weights of plaice at to the " " eyed feather, with fully developed metallic each unit of length from various fi shing grounds have also lustre, of the mature peacock's " fan." He then described 13 bee n d etermined. Taking H eincke 's formula w = k the retrogressive changes leading from the " eyed ". feathers 100 to the modified feathers of the back a nd margin of the where w is the weight in grams a nd I the length in centi " fan." m etres, the monthly variations in the value of /z have been Coccidia and Coccidiosis in Birds. ca lculated for several of the grounds. The value shows a Dr. H . B. Fantham described his observations on the maximum in July, and the minimum appears to be in life c ycle of the sporozoon Eimeria (Coccidimn) avium, J a nuary, at which time of the year very little food is found in the s tomachs of the plaice. which produces a form of " enteritis " in grouse, fowls, in young birds. Resistant A considerable section of the report is occupied by papers and pheasants, especially ·oocysts of the parasite are voided in the freces of the on hydrographical work done in the Irish Sea by Mr. acquired b y other birds in their Johnstone and Dr. H. Bassett. It is doubtful, however, infected birds, and are oocyst conta ins four sporocysts, whether the comparatively . slender d ata contained in the food or drink. A mature ?ctive motile sporozoites. After pa pers. of the latter writer can be usefully employed in the in each of which are two way suggested by him, in connection with the prediction of the oocysts have been swallowed by a bird, the cyst wall clima tic conditions over extended p eriods of time. Very is softened by the pancreatic juice, the sporozoites creep much more research will be. necessary before such predic out a nd .penetrate the epithelial cells of the duodenum, in tions can have any but a speculative value. which they become rounded and grow, feeding passively The report concludes with a paper by Prof. Herdman, on the host cell. After attaining a certa in size, the e-now a schizont Mr. A. Scott, and Mr. Dakin on plankton work carried nucleus a nd protoplasm of the parasit out off the Isle of Man in 1909. The paper as a whole divides into a cluster of merozoites arranged en barillet, an orange. V ery little residual tends to confirm the doubts, which h ave often been i. e. like the segments of expressed , as to the value of the qua ntita tive methods of protoplasm r emains after the formation of merozoites. plankton work, as at present practised. Until some trust These sma ll, vermicular merozoites glide a way and invade worthy in strument has been devi sed for a ccurately measur other cells, within which they grow to schizonts and ing the qua ntity of water which has passed through the multiply. A number of generations of merozoites is pro the destruction of the epithelium net on each occasion, the elabora te methods of counting the duced in this way, and or/:(;, ni sms captured would hardly seem to repay the time and the derangements resulting therefrom in some cases which must necessarily be employed upon them. cause death of the host. In most insta nces some mero zoites p ass down into the creca, where · they grow and multiply, producing intense inflammation. Sooner or later a limit is r eached, both to the power of the bird to provide ZOOLOGY A.T THE BRITISH ASSOCIATION. nourishment for the parasites and to the multiplicative THE attendance of zoologists at the meetings of Section capacity of the parasite itself, and then s exual forms are D was affected by the fact tha t the International produced. Some of the organisms become large and con Congress of Zoology at Graz a nd the International Con tain much reserve food material. These are the macro gress of Entomology at Brussels had .taken place so gametocytes, each of which, after the m aturation changes, recently. These meetings abroad were probably responsible becomes a single macrogamcte. Slight ly smaller parasites, for the absence of a few of those who in previous years with little or no reserve material, undergo nuclear multi have contributed papers to th e section. The programme, plication and give rise to many minute biflagellate micro bein g a little less crowded tha n usual, was taken at a gametes, which disperse and swim away in search of more comfortable pace, and reasona ble- time was available macrogametes. Each of the latter has precociously for discussion and remarks on the va rious subjects under invested itself with a cyst wall, in which a micropyle is NO. 2 I 39, VOL, 84] © 1910 Nature Publishing Group OCTOBER 27, 1910] NATURE 549 left for the e ntry of the microgamete. One microgamete a bsorb protein from them . When fully impregnated with only fu ses with the macroga mete, and then the oocyst wall nutri tive ma teria l they fall back into the hremoccel as is completed by closure of the micropyle. This series of oval g lassy cells, and the protein contents are gradually cha nges, from infection to th e formation of oocysts, ex absorbed during the winter fast. tends o ver about eight or ten d ays in the grouse. At fir st t he oocysts are uninucleate, a nd their contents com Sex and Immunity.

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