ZOOLOGY AND BOTANY, MICKOSCOPY, ETC. 45 



support whatever to tlie suggestion that tlie coelom-sacs of Myriopods 

 are enterocoelic in origin, as in Annelids the ccelom arises by the split- 

 tino- of the mesoderm. In Scolopcndra there are two kinds of mesodermal 

 lymphoid organs, (1) the lymph-bodies of the head which are present 

 only in the embryo, and (2) apparently replacing these, the lymphatic 

 bands (filaments aeides of Duboscq) of the adult. The author brings 

 forward reasons for believing that the latter are morphologically as 

 well as physiologically tho equivalents of the nephridia of Annelids, 

 while he further compares the cephalic lymph-bodies ( = the sub-ceso- 

 phageal bodies of insects) to the green glands of Crustacea, and with 

 less certainty to the primitive kidneys of Annelids. Again, the author 

 finds that the brain of Scolopendra consists of a preoral syncerebrum, 

 homologous with the Annelid brain, plus three pairs of postoral ganglia. 

 The "head" in Diplopoda, Chilopoda and Insecta consists of the acron 

 united to six anterior metameres. This is true also of the Crustacea, 

 but in the Arachnoidea and Gigantostraca another segment is added. A 

 new classification of Arthropods is proposed, based in part upon the 

 number of segments composing the head, and in part upon the nature 

 of the appendages. In regard to the question of the origin of the mid- 

 gut in Myriopods and Insects generally, the author considers that in 

 Scolopendra and in many Apterygota the primary endoderm is partly 

 converted into embryonic yolk-cells, and partly forms the permanent 

 endoderm lining the mid-gut ; but in the majority of Pterygota the 

 primary endoderm is entirely converted into the embryonic yolk-cells, 

 and the mid-gut is therefore lined by ectoderm. But this does not 

 affect the fact that the mid-gut is phylogenetically homologous through- 

 out these groups. 



5. Arachnida. 



Bites of Latrodectus 13-guttatus.* — L. Bordas has made a number 

 of experiments in regard to the bites of this spider, popularly called 

 malmignatte. In some countries, e.g. Corsica, they are believed to be 

 fatal to man and large animals ; the author finds no evidence of this. 

 Bites on arm and wrist were followed by slight inflammation and much 

 itching, but by no serious symptoms. To insects — flies, beetles, 

 Orthoptera — the bite is rapidly fatal. The author describes the struc- 

 ture of the poison-glands. 



Monograph, on Spiders of Germany, f — W. Bosenberg begins what 

 promises to be a very valuable monograph. The first part gives 

 detailed diagnostic tables, and goes on to a description of the members 

 of the families Euetriodae, Uloboroidas, Tetragnathoidae, and Theridioidae. 



In the introduction the author directs attention to the great varia- 

 bility that makes identification often difficult. Abundant food may 

 double the usual size, and colour varies according to locality. Ex- 

 periments with Tegeneria domcsilca and Theridium corroborated this 

 observation. In general terms it may be said that in dark places the 

 characteristic colour and markings tend to be lost. Even the genital 

 appendages change not a little according to the functional state. 



'• Comptes Bendus, exxxiii. (1901) pp. 953-5. 



f Zoologica, xiv. Heft 35' (1901) 95 pp., 10 pis. and 11 figs. 



