ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 679 



Primitive Schizopod Crustacean.* — H, Woodward gives an 

 account of some additional specimens of Pygocephalvs cooperi, a primi- 

 tive Schizopod crustacean from the Coal measures. Huxley first described 

 this form in 1857, and all the specimens that have been examined since 

 then have merely served to amplify and corroborate his observations in 

 regard to the males. But among some specimens recently obtained 

 from a bed of clay-ironstone nodules at Coseley, near Dudley, were two 

 which were clearly female. These show most distinctly, on the ventral 

 aspect of the thorax, the presence of a brood -pouch or marsupium, con- 

 sisting of 6 or 7 broad scale-like imbricated plates, the " oostegites." 

 Such structures are well known in many recent Crustaceans, but have 

 not hitherto been preserved in any fossil form. Two less perfect females 

 have since been detected in the British Museum collection. 



Annulata. 



New Polychaeta from Massachusetts.! — J. Percy Moore describes 

 Arabella spinifera, Praxillella trkirrata, Cirratulus parvus, and Amphi- 

 trite attemiata, all of them new species from the south-eastern coast of 

 Massachusetts. 



Operculum of Spirorbis.| — E. Elsler describes the structure of the 

 operculum of Spirorbis and the modifications it undergoes when used as 

 a brood chamber. For his investigations he used two species, S. corru- 

 gatus Montagu and S. pusillum. He finds that the operculum is 

 derived from a modified gill-ray and consists of a simple stalked vesicle, 

 the epithelium of which secretes a firm cuticle with localised secretion of 

 lime. When the operculum functions as a brood-chamber the eggs lie, 

 not, as is usually stated, within the ampulla, but between the hard cuti- 

 cular layer and the epithelium which is retracted from it. During 

 incubation the epithelium secretes a new cuticular layer. The eggs 

 escape from the body cavity in some way as yet undetermined, and 

 make their way into the brood chamber from without, possibly by the 

 fissure through which the embryos make their exit, but this could not 

 be demonstrated. The operculum may function thus several times in 

 the hfe of an individual, but the repetition is attended by certain modifi- 

 cations. The processes of shedding and renewing the cuticular layer 

 are common to all species of Spirorbis, and are not connected with repro- 

 duction. The functioning of the operculum as a brood-chamber is 

 apparently a later character, made possible by these processes and 

 acquired only by some species. 



Neotropical 01igoch8eta.§ — L. Cognetti de Martiis gives new records 

 of several forms belonging to the families Megascolecidge, Glossosco- 

 lecidae, and Lumbricidai. Amongst them are Dichogaster tristani sp. n., 

 from San Jose de Costa Rica, found under the bark of a rotten tree, and 

 Anteoides desartsii sp. n., from North Paraguay. 



* Geol. Mag., iv. (1907) pp. 400-7 (1 pi. and 3 figs.), 

 t Proc. Acad. Nat. Sci. Philadelphia, Iviii. (1906) pp. 501-8 (1 pi.). 

 % Zeitschr. wiss. Zool., Ixxxvii. pp. 601-43 (1 pi. and 13 figs.) ; 



§ Atti R. Accad. Sci. Torino, xlii. (1907) pp. 781-800 (1 pL). 



