9 
Lutz" regards the small forms as male and the large as female. 
He has never seen evidence of conjugation of the trophozoites in the 
blood of the host. The intermediate host is unknown. 
H^MOGREGARINID^ OF TURTLES AND CROCODILES. 
A large number of hsemogregarines have been described in turtles. 
Hxmogregarina stepanovi Danielewsky has been carefully studied by 
Danielewsky, and in its sexual development by Siegel.^ 
In Hsemogregarina stepanovi the gametocytes, according to Siegel, 
are the elongated trophozoites which are bent into a U shape on 
account of their length being greater than that of the red blood cell 
which they inhabit. Schizogony occurs as in other hsemogregarines. 
There is no dimorphism of the schizonts. The invertebrate host is a 
leech, in the gut of which the gametocytes develop and fertilization 
takes place. The ookinet which develops from the zygote invades 
the intestinal wall and enters the esophageal glands, where elongated 
sporozoites are formed. Infection of the turtle, to which the leech 
next attaches itself, is said to take place in a manner similar to the 
malarial infection from mosquitoes. Siegel believes that the ovary 
and eggs of the leech may be invaded by the sporozoites, and the 
next generation of leeches thus infected. 
H^MOGREGARINID^ OF FISHES. 
About twelve species are known. Hspmogregarina higemina, from 
the blood of blennies {Blennius pholis) , has been described by Laveran 
and Mesnil.^ In the nonsexual multiplication of this parasite by 
binary fission a resemblance to the manner of multiplication in 
piroplasma is observed, and incidentally to that in trypanosomes. In 
this connection it is interesting to note that trypanosomes have been 
found very frequently in the blood of fishes, wliich also harbor hsemo- 
gregarines. The group is as yet imperfectly known. The mode of 
transmission of the infection has not been determined. 
In all hsemogregarines of cold-blooded animals wliich have been 
studied , nonsexual multiplication or schizogony takes place in the red 
blood corpuscles, usually in some internal organ. The merozoites, 
when set free, invade other red blood cells, and increase considerably 
in size before reaching maturity. 
«Lutz, A.: Ueber die Drepanidien der Schlangen. Ein Beitrag zur Kenntniss des 
Hamosporidien. Centblt. f. Bakt., 1. Abt., vol. 29, 1901, pp. 390-398. 
b Siegel; Die geschlechtliche Entwicklung von Hxmogregarina stepanovi in Riisse- 
legel Placohdella catenigera. Arch. f. Protistenkde., 1903, Bd. 2, H. 3, pp. 339-342. 
c Laveran, A., & Mesnil, F.: Deux hemogregarines nouvelles des poissons. C. R. 
de BAcad. des Sci., vol. 133, 1901, pp. 572-577. 
