280 SUMMARY OF CUREENT RESEARCHES RELATING TO 



tissues, either via the skin or the upper alimentary tract, they make 

 their way to the portal veins, where they become adult males and 

 females. In S. mansoiii the lateral-spined ova are excreted mainly in 

 the fa3ces, less commonly in the urine as well. The life-cycle is as 

 before, but the intermediate host is a species of Planorbis. In internal 

 structure the two species are markedly different, as is shown in detail. 

 Wherever Planorhis is the common snail there will be rectal Bilharziasis ; 

 wherever BuUinus abounds the urinary form of the disease will be most 

 prevalent. The prophylactic measures are destroying the ova in the 

 excreta, destroying the molluscs, and purifying the contaminated water 

 supplies. J. A. T. 



Diagnosis of Parasites in Man. — Robert W. Hegner and 

 William W. Cort {Waverly Press, Baltimore, 1921, 1-72, 8 pis.). 

 The authors have prepared a very useful bulletin of the common 

 Protozoa and Worms parasitic in man. It is compact and clear, and 

 should be a great boon to students, as well as to physicians and public . 

 health workers. Rarities are of course left out, but all the very 

 important forms are dealt with in a way that should admit of identifi- 

 cation. The figures are careful and effective. We venture to suo'gest 

 that subsequent editions should include the most important ecto- 

 parasites. J. A. T. 



Distome Larvae in Gut-wall of Dytiscus marginalis. — A. Ch. 

 HoLLANDE {Arch. Zool. Exper., 1920, 59, 543-63, 12 figs.). The 

 presence of numerous larval distomes does not seem very hurtful. The 

 excretory tubules seem able to get rid of the toxins. There are many 

 multiplying cells in the Malpighian tubes. The adipose cells are not 

 much altered, but some show hypertrophied and budding nuclei. 

 Around the encysted parasites considerable tissue changes are seen. 

 There is a thick mantle of phagocytes ; some peri-intestinal muscle 

 fibres partly surround the cyst ; a membrane is formed around the 

 cyst, and is probably due to the peritoneum. The surrounding of the 

 cysts, especially the phagocytic layer, may be regarded as arresting or 

 neutralizing the parasite's toxins. J. A. T. 



Revision of Indian Species of Phyllobothrium. — T. Southwell 

 and B. Prashad {Records Indian Museum, 1920, 19, 1-7, 1 pi.). 

 Most members of this genus infest fishes, but one has been reported 

 from a snake, one from the dolpliin, and one from Sowerby's whale. 

 The bothridia are sessile, very mobile, with puckered edges. A note- 

 wortliy point is the presence of supplemental discs on the bothridia of 

 some species. The authors revise five Indian species. J. A. T. 



Echinoderma. 



Rare Anomaly in Astropecten aurantiacus. — Gr. Zirpolo {Publ. 

 Staz. Zool. Napoli, 1918, 1, 31-58, 3 pis. 10 figs.). Four specime'iis 

 with four arms, instead of the normal five. The occurrence of four 

 appears to be due to the loss of one arm with a considerable part of the 

 disc, for in this case the missing arm is not regenerated. A process of 

 cicatrization occurs. In the area of lesion the plates that are formed 



