200 SUMMARY OF CURRENT RESEARCHES RELATING TO 



tepJialns bursa, when hungry, fix at once on the host. After three to 

 five days the males seek anchored females, a number in succession. As 

 in other species the males remain upon the host after the females drop 

 off, which accounts for the predominance of male ticks on a host. 



J. A. T. 



Spermatogenesis in Ixodes ricinus. — Erik Nordenskiold {Para- 

 sitology, 1920, 12, 159-66, 1 pL). The spermatogonium has twenty- 

 eight chromosomes at mitosis ; the centrosome appears then as a very 

 conspicuous triangular corpuscle. The spermatocytes of the first and 

 second order are described. The spermatid undergoes intricate meta- 

 morphosis, affecting nucleus, cytoplasm, centrosome and mitochondria. 

 'The outcome of the changes which the author describes, not very 

 readily summarized, is the formation of an atypical spermatozoon, not 

 easily comparable with the common spermatozoon type. It shows a rod- 

 like, laterally placed nucleus, a conical centrosomal corpuscle united with 

 the nucleus, and a plasma rod with a stainable core. J. A. T. 



Patal Occurrence of a Pentastomid in Man. — Monziols, 

 CoLLiGNON, and Jean Roy {G. R. Soc. Biol., 1920, 83, 28-9). A 

 Senegalese tirailleur died in hospital at Constantinople of severe icteritis, 

 accompanied by cerebral excitement. His liver, of small size, showed in 

 the biliary canaliculi an enormous number of specimens of Poro- 

 cephaliis armillattis, marked by four simple hooks and twenty to twenty- 

 two rings. The adult is found in the trachea of large snakes ; the larva 

 occurs in monkeys and in man in the deeply situated organs. The 

 epidermis of the specimens is chitinogenous ; connective tissue occupies 

 the place of the dermis and the interstices ; the walls of the intestine 

 show deep folds ; there was no trace of reproductive, respiratory, nervous, 

 or sensory systems ; there is a strongly developed muscular system of 

 peripheral fibres (longitudinal and annular) and of deep fibres around 

 the intestine. This is the second instance of this parasite in a Sene- 

 galese. J. A. T. 



e. Crustacea. 



Fresh-water Harpacticids from Peru. — Tir. Delachaux (Revue 

 iSuisse Zool., 1918, 26, 117-27, 1 pi.). Nine species of Ganlhocamptus, 

 including three new ones. The occurrence of Mar sen oh lotus natico- 

 chensis is interesting as regards geographical distribution. Attention is 

 directed to a representative of the genus Godetella, whicli is allied to the 

 European WoJterstorffia and to the Asiatic Marshia, the three genera 

 being primitive types wliich have undergone a parallel evolution on three 

 continents. The Harpacticids do not live among the plankton of the 

 open water of the lake, but in shallow water among aquatic plants and 

 on stones. J. A. T. 



Annulata. 



Structure of Sabellids and Serpulids. — W. C. ^PIntosh {Ann. 

 3Ia(/. Nat. Hist., 1918, 2, 1-59, 6 pis.). Sabellid structure is illustrated 

 mainly in reference to Bispira voluiacornis, attention l)eing directed to 



