BY T. HARVEY JOHNSTON. 405 



The corpuscles were froin 18-20 /^c long, by 10 or 1 1 /a broad, 

 with nuclei averaging 7 by 4-5 /x. The parasites varied from 10 

 to 19/iin length, and from 1-5 to 5 or 6 /x in greatest breadth. 

 The largest forms measured '20 fx by 4/x, and 17-5 /lc by 6 /x; whilst 

 the smallest were 12 by 1-5 fx, and 10 by 4 /x. 



Even the largest hfemogregarines, some of which occupied 

 nearly the whole of the available space in the host-cell, i.e., the 

 nucleus excluded, did not cause any distortion of the erythrocyte, 

 though the host-nucleus was usually displaced, even by moderately 

 large parasites. Only exceptionally was its position so much 

 altered that it rested against the edge of the red corpuscle. 



Only one very young form, aV)out 6 by 2 /x, was detected. It 

 was placed transversely, towards one end of the host-cell. 

 Crescentic parasites were rather uncommon, adult sporonts 

 greatly predominating. The last varied considerably in shape. 

 iSome were club-shaped, with a very wide rounded anterior part 

 which tapered to a much narrower, though still blunt, posteiior 

 end. Others were very long and somewhat narrow, the posterior 

 end being bent round in an open curve. Others again were 

 nearly uniform in breadth throughout, whilst still others pos- 

 sessed the typical adult-form in which the " tail " was bent 

 round in such a way as to lie close to the " body." The parasites 

 were usually of greatest breadth in the region of the nucleus, a 

 distinct bulging being seen on the inner {i.e., the concave) side. 



The nucleus was generally broad and band-like, though occa- 

 sionally it was small and irregular, or rounded. Its position 

 was somewhat nearer one end. 



The capsule was somewhat similar to that seen in //. shattocki, 

 but appeared to be more delicate. 



In brief, the main difference between H. morelice and H. 

 shattocki is, that the sporonts of the former are rather shorter 

 and much wider. H. pococki Sambon and Seligmann, from 

 Python molurus Linn., is evidently a close ally to this species. 



The type-slide has been presented to the Australian Museum, 

 Sydney. 



