300 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
if the bugs were not fed again, the flagellates after multiplying rounded 
up again. When bugs heavily infected with flagellates are allowed to 
feed on clean human blood, in a large percentage the flagellates are 
destroyed and disappear. If the flagellates had succeeded in rounding 
up, they were able to multiply when the bug fed again. In what stage 
is the parasite likely to enter the human skin ? The author refers to 
the work of Cornwall and of Mrs. Adie on the “ thick tail ” stage of 
the parasite, which is an intracellular stage. The author confirms 
Mrs. Adie’s discovery, and has observed the process of thick tail forma- 
tion in the cell, and the division of the parasite within the sheath. As 
the thick tail formation is not seen in the gut of any other blood- 
sucking insect, and the change does not take place when the flagellates 
in a culture are treated with the mid-gut of either Pulex irritans or 
Pediculus hominis, the author regards this as “ the final proof that Gimex 
is the true invertebrate host of Herpetomonas donovaniP It is believed 
that H. donovani is acquired by man when an infected bug is crushed 
on the skin, the infective stage gaining entrance into the puncture pro- 
duced by the proboscis of the crushed bug, or into a minute abrasion. 
Regarding H. tropica also, a similar intracellular stage is described. 
The flagellates here also, on entering a cell of the mid-gut of Cime$, 
develop a sheath, and then curling up become round ; the movements 
of the flagellum within the sheath produce the characteristic thick tail. 
The encapsuled flagellate while coiled up in its capsule divides, and 
several daughter flagellates are produced (intracellular multiplication), 
which in time leave the cell by the rupture of the capsule. In this case 
also the infected bug is supposed to carry the infection by being 
crushed on the skin, no parasites having been found in the salivary 
glands. B. L. B. 
Giardia (Lamblia) intestinalis in Children. — K. F. Maxcy 
(Bulletin Johns Hopkins Hospital , 1921, 32, 166-70). This Protozoon 
parasite is present in the intestinal tract of a large percentage of 
apparently normal children. It is rarely found before the first year. 
The percentage of infestations appears to be much higher in childhood 
than in adult life. In certain rare instances the parasite may be 
responsible for some intestinal disturbance, but the point has not yet 
been firmly established. There is no evidence as yet that any of the 
drugs used to clear out Giardia is of the slightest use. J. A. T. 
Gregarina ssenuridis and its Host.— Jean Delphy ( Comptes 
Rendus Acad. Sci, 1922, 174 , 1644-6, 1 fig.). This Gregarine 
described by Kolliker in 1848 does not seem to have been seen since, 
but it is very common in a limicolous marine Lumbricid, Pachydrilus 
verrucosus ( = Kolliker’s Ssenuris variegata). The parasites occur right 
through the body, all the year round. The trophozoite stage is rare ; 
it must be passed through quickly. The trophozoites are often longitu- 
dinally apposed in syzygy ; but isolated individuals also occur. There is 
a Monocystis stage and a Zygocystis stage. The parasite is very different 
from Urospora ssenuridis Ray Lancaster, which occurs in Tubifex. Its 
spores are not appendiculate. There may, in rare cases, be solitary 
