46 SPOLIA ZEYLAMCA. 



I was quite unable to identif j- these organisms, never having seen 

 anything like them, but Professor Kailliet of Alfort, to whom I 

 sent them, recognized them at once as specimens of Sarcocystis, 

 one of the order Sarcosporidia, which Biaun* places as the sixth 

 and last order of the class Sporozoa, whilst Wasiliewskif places 

 it as an appendix to the class. 



The organisms were somewhat pointed, though not very sharply, 

 at either end. One or two ends were truncated. The largest of 

 them measured 150 mm. in length, 5 mm. in breadth, and '6 mm. 

 in thickness, the thickest part being in the middle liae. 



In transverse section the animal is seen to consist of a number 

 of polyhedral chambers with granular contents. The peripheral 

 chambers were completely full, stained deeply, and showed a very 

 fine granulation, like that of protoplasm. The central chambers 

 were in some cases empty or almost empty. The others contained 

 small corpuscles, which I take to be spores, but the state of preser- 

 vation did not permit of certainty on this point. The outer 

 coating consists of two sheaths, an outer one which is a continuous 

 coating, and an inner one directly continuous with the partitions 

 which divide one chamber from the next. Close under the 

 coating in some places can be seen a few smaller chambers, but 

 these may be simply the narrow ends of some of the others. The 

 partitions between the chambers look like connective tissue. I 

 am inclined to consider that this species is Sarcocystis tenella^ 

 Railliet. 



It is just sixty years since Von MiescherJ first described 

 certain white cylindrical bodies lying in the voluntary muscles of 

 the house-mouse, and since that date numerous other observers 

 have described similar bodies lying in the muscles, and more 

 rarely in the connective tissue, of mammals, birds, and reptiles. 

 Nothing is definitely known as to the means by which the various 

 hosts — many of which are confined to a vegetable diet — become 

 infected. The parasite seems to first appear as a cell-parasite 

 within a muf>cle-cell, which retains its striation and seems but 

 slightly affected. The nucleus of the Sarcocystis then undergoes 

 division, and we find later a poly-nucleated organism which 

 gradually breaks up into a corresponding number of chambers. 

 The nuclei and protoplasm of these chambers then break up into 

 an enormous number of minute spores, often sickle-shaped, some 

 of which have been descrii>ed as having two fiagella at one end or 

 oneflagelliim at each end. The fate of these spores orsporozoitesis 

 varied, and not very definitely known. Some undoubtedly fail to 



* "Die thierii^clien Parasiten des Menschen." Wiirzburgc, 190H. 

 t " Sporozoenkunde." Jena, 1896. 

 X Verh. Ges. Basel, v.. 1848. p. 198. 



