Miscellaneous. 405 



winged insects quit the capituli on which they had been developed 

 and seek to escape from the bell glass. He then inserted a frag- 

 ment of poplar-bark under the bell, when the Aphides at once col- 

 lected upon it and began producing sexual individuals. Tho same 

 thing was done by individuals which had been allowed to fly and 

 had collected on the window-panes. The poplars in the garden 

 were at the same time covered with these Aphides. 



In conclusion M. Lichtenstein calls attention to a possible objec- 

 tion to his experiment, viz. that he did not grow the Filago from 

 seed under cover — and promises to remedy this defect next year. — 

 Comptes Rendus, August 9, 1880, p. 339. 



On the Ciliated Embryo of Bilharzia. By M. J. Chates. 



The regularly oval egg of Bilharzia (B. hamiatobia, Cobb., the 

 African Trematode parasite in the blood of man) presents no traces 

 of striae or flutings ; but at one of its poles it bears a conical pro- 

 longation *. The segmentation of the vitellus takes place rapidly, 

 and we soon witness the formation of an embryo of very charac- 

 teristic aspect. 



Clothed with a cuticle, from which innumerable vibratile cilia 

 emerge, the young larva appears like an infusory contained within 

 the egg, and the interior mass of which does not yet present any 

 indication of differentiation ; externally the contours become more 

 strongly marked, and a sort of mamilla (proboscis) begins to indi- 

 cate the future cephalic region. This general state usually persists 

 until the period of exclusion f ; aud the latter is announced by 

 various precurrent acts, into the details of which I cannot enter, 

 and then makes itself plain by important organic modifications : 

 beneath the proboscidian zone there is sketched out a caecum, which 

 plunges vertically into the somatic mass, and soon attains consi- 

 derable dimensions ; on its lateral parts appear secondary diverti- 

 cula, which together form a rather complex whole, whilst at dif- 

 ferent parts of the body, and especially in the tegumentary layer, 

 elegant vasculiform streaks ramify. 



During this time phenomena of a very different kind appear 

 towards the posterior extremity of the body ; peculiar formations, 

 generally spheroidal, begin to show themselves there, and increase 

 rapidly in number and volume. Are we to see in these only 

 " sarcode globules " ? Such a hypothesis disappears before the 

 application of a method rendered classical by important researches 

 (Kanvier, Certes, &c.) ; the mode of grouping of the nitrogenous, 



* In all the eggs that I have been able to examme, this prolongation 

 was distinctly axial ; but it is well known that Bilharz has described a 

 second kind of ovules with the point lateral, in which, indeed, Sonnino 

 even appears to find an indication of an actual specific duality. 



t Sometimes, however, one can distinguish the first lineaments of 

 the caeca even in the embryo still contained within the egg. 



