ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
45 
end by a yellowish filament, 1*5 mm. long. Its substance is fibrous and 
it is also distinguished by its appearance from the shell- substance of the 
egg, to which the filaments are fixed by a finely granular mass. These 
filaments appear to be secreted by well-developed dermal glands, which 
are placed near the genital orifice. The embryos enclosed in the eggs 
are, save for the difference in size and the development of the reproduc- 
tive organs, exactly like the adults. 
Anatomy of Distomum fabaceum.* — Mr. J. M. Stedman has some 
notes on the anatomy of this Trematode, which was found in the large 
intestine of a Manatee ; the author’s account is purely descriptive. 
External Differences in Species of Nematobothrium. f — M. I?. 
Moniez reports that a large number of specimens of a new species of 
N ematobotkrium — which he calls N. Guernei — were found on fifty-three 
specimens of Thynnus alalonga dredged during the voyage of the Prince 
of Monaco’s yacht ‘ Hirondelle.’ The specimens were from O’ 3 to 0*5 
metre long. At first sight, it was difficult to say whether the parasite 
was a Trematode or a Nematode. Nor did the investigation of the in- 
ternal structure enable the author to at once determine the question. 
At the anterior end of the body and at the point ordinarily occupied by 
the mouth there are two genital orifices, very distinct from one another 
and placed one above the other, as is the case in many Cestodes. The 
male apparatus is formed of a penial pouch, and is continued by a 
sperm-duct into two immense testicular tubes ; the oviduct is extremely 
long and folded several times along the whole length of the body, and it 
is continued into an ovary which presents the same peculiarity. 
Near the hinder extremity is the orifice of the water-vascular appa- 
ratus, which is continuous with a tube of thick walls, very wide, and 
extending without any ramifications as far as the anterior part of the 
body. These are the only organs which the author has as yet been able 
to make out. But very large nerve-cells, like those already noticed in 
Trematodes, have been frequently seen in the tissues. The specimens 
found in the gills were in the form of cysts containing two individuals 
which were very delicate anteriorly but greatly swollen in the remaining 
part of their body ; their structure, however, shows they belong to the 
same species as the others ; the polymorphism appears to be due to the 
difference in the difficulty of development, according to the spot at which 
the embryos are fixed. 
Cysticercoids of Freshwater Crustacea. :J — Herr Al. Mrazek de- 
scribes several cysticercoids with caudal appendages from freshwater 
Crustacea, and diminishes the number of species of Tsenia whose inter- 
mediate hosts were unknown. Cysticercoids were obtained from 80 per 
cent, of examples of Cyclops agilis examined. They lie freely in the 
body-cavity. The body is lens-shaped, and 0 * 12-0 * 18 mm. in diameter ; 
it is covered by a completely hyaline layer, and the subjacent cuticle 
has numerous pore-canaliculi ; the rostellum has eight or nine hooks. 
The parasites are found in both males and females, and in the latter the 
* Proc. Amer. Soc. Microscopists, xi. (1889) pp. 85-101 (3 pis.). 
f Comptes Rendus, cxi. (1890) pp. 833-6. 
X Verhandl. der Kgl. Ges. der Wiss. Prag, i. (1890) pp. 226-48 (1 pi.). See 
Ceutralbl. f. Bakteriol. u. Parasitenk., viii. (1890) pp. 628-30. 
