290 
Haemogregarines in Snakes 
hosts and parasites (p. 292), which is as exhaustive as I have been able 
to make it. I may add that I have experienced considerable difficulty 
with the work of Sambon. As far as I am aware, Sambon has up to the 
present published merely a brief note in the Lancet (1907). Figures of 
his findings have been given, however, by Manson (1907), where many 
of the parasites are attributed to Sambon and Seligmann. Manson 
also gives some snake haemogregarines of which I can find no other 
mention. The information regarding them is, to say the least, scanty. 
In one place a new species is described from a “ Mexican snake ” under 
the name “ Haemogregarina brumpti Sambon.” 
It may be remarked here that all the blood parasites of snakes— 
described under the names Haemogregarina, Danilewskya, Drepanidium, 
etc.—probably belong to the genus Haemogregarina, though perhaps in 
part also to the genus Karyolysus. The genus Haemogregarina was 
created by Danilewsky in 1885 —Danilewskya Labbe 1894 being a 
synonym. If it be subsequently found that all the haemogregarines of 
snakes are really of the same species—which I think by no means im-* 
possible—then the correct name for the parasites is Haemogregarina 
serpentium Lutz. 
I. Haemogregarina sp. from Boa constrictor. 
(Plate XX, Figs. 1—13.) 
This organism was obtained from a Brazilian Boa constrictor which 
had died of canker of the mouth. It is possibly identical with 
Drepanidium serpentium Lutz 1901 and Haemogregarina terzii Sambon 
1907. 
The parasites were very numerous, both in the general circulation 
and in the internal organs. 
Small forms (Plate XX, Figs. 1, 2) were very uncommon. The com¬ 
monest forms were those shown in Figs. 3—6. It will be seen that there 
are two distinct types of parasite—a long form with a recurved “ tail ” 
(Figs, 3, 4) and a stumpy form with rounded ends, and often with two 
vacuoles (Figs. 5, 6). The latter were not so frequently seen as the 
former. 
Very large forms were fairly common, and many appeared to have 
arisen by the growth of the “ tailed ” forms (Figs. 7, 8). They attained 
a length of from 13ft to 15ft, and often appeared to have outgrown the 
corpuscles in which they had developed (Fig. 9). 
