ZOOLOGY AND BOTANY, MICROSCOPY, F/IC. 87 



principle, with that of Diplorystis. In both forms the haploid number 

 of chromosomes is found in every nucleus throughout the entire life- 

 history, with the single exception of the zygote nucleus. This is a diploid 

 nucleus, containing two haploid groups of chromosomes derived from the 

 two gamete nuclei which entered into its formation. The division of 

 this nucleus is, in both Aggregata and Diflocystis, a reduction division, 

 which reduces the diploid number to the haploid once more. From the 

 point of view of the chromosomes, it is thus clear that the first division 

 of the sporont nucleus of Aggregata is not homologous with the first 

 division of the " sporont " (gamont) nucleus of Diplocystis, but with the 

 first division of its spore nucleus— since these are the divisions during 

 which the chromosome numbers are halved." 



It should be noted (1) that this is the first demonstration of a chro- 

 mosome cycle in the Protista ; and (2) that the reduction does not occur 

 during gametogenesis. The authors regard the supposition that reduc- 

 tion occurs during gametogenesis in the Coccidia and Gregarines as an 

 incorrect analogy drawn from other animals. 



New Polycystid Gregarine.* — Shigemi Ishii describes from the 

 food-canal of a Diplopod {Fontaneria coarctata Pocock) a curious Grega- 

 rine — Spirosoma caudata g. et sp. n. — showing conspicuous spiral striation 

 in the posterior part of the body. The sporonts are always soUtary. 

 The protomerite is short and generally conical, with a pore-like structure 

 at the apex in the younger stages at least. The deutomerite is large and 

 elongate, divisible into two parts, the broad anterior and the narrow 

 posterior. The epicyte of the protomerite and of the broad anterior 

 part of the deutomerite shows the ordinary fine longitudinal striation, 

 while in the tail this takes a spiral course and is less dense. The sarco- 

 cyte is well developed. The endocyte is dense. The nucleus in the 

 broad anterior part of the deutomerite is large and vesicular, containinLT 

 a single large spherical karyosome, sometimes with a small vacuole. 



Hsematozoa of Australian Batrachians.j — J. B. Cleland continues 

 his studies of these, and has examined blood films from eighteen species. 

 Only two species showed Hsematozoa, Hyla carulea showing Haemo- 

 gregarina {LanTcesterella) hylae, and Lmnodynastes tasmamensis showing 

 Trypanosoma rotatorum in very pleomorphic representation. 



* Annot. Zool. Japon, ix. (1915) pp. 7-9 (2 figs.). 



t Journ. Proc. Roy. Soc, New South Wales, xlviii. (1915) pp. 412-4. 



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