GANYMEDES ANASPIDIS (nOV. GEN., NOV. SP.). 157 



cut of individual parasites, and of the gut and liver of the 

 host. Most of these were stained with iron hasmatoxylin, 

 some with Ehrlich's haematoxylin and eosin, and some with 

 methyl-blue eosin by Mann's method. Iron haematoxylin 

 was the best for most purposes, but Mann's method was very 

 interesting in revealing some of the complexity of the purely 

 vegetative processes that take place in the nucleus and 

 nucleolus. 



It was of course impossible to get auy Anaspides over to 

 England alive, and thus several questions of structure and 

 life-history which could probably have been easily elucidated 

 by observations and cultures of the living Gi-egarine, have 

 had to be left to await the verdict of some investigator who 

 has not got the Tropics between himself and the source of 

 his material. 



General Account (Life-history, Habitat, Etc.). 



As above mentioned, Granymedes is a parasite of the 

 Syncaridan Crustacean Anaspides tasmaniae, inhabiting 

 various portions of its digestive tract. Before proceeding to 

 a detailed account of its structure, it will be best here to 

 give a brief general survey of its life-history, as far as such a 

 continuous record can be pieced together from the mere snap- 

 shots which are all that preserved material can give. 



I came across no sporozoite stage. The smallest Gregarines 

 found were only about one-eighth the length of the full- 

 grown motile trophozoite, but otherwise similar in every 

 way. These elongated motile forms, obviously belonging 

 to the class Gregarinida, are in what I shall call the first 

 trophic period, which is spent within the very long mid- 

 gut of the host. Here some are attached to the epithelium 

 (fig. 9), but the majority are found free in the lumen. If 

 the host has recently been feeding, the gut is crammed with 

 sand-grains and organic particles; and when this is the case, 

 the parasites collect between this food-mass and the gut-wall. 



