ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
475 
appear to be in the Tristomida) any duct analogous to the vitello- 
intestinal canal of many Polystomidae. 
Tristomum histiophori.* — Prof. F. Jeffrey Bell describes a new 
species of Trematode under the above name, and points out its differ- 
ences from T. coccineum, to which it is closely allied, and which has 
been found on Xiphias , a close ally of Histiophorus brevirostris, the host of 
the new species. 
Remarkable Flat- worm Parasitic in Golden Frog.f — Prof. W. A. 
Haswell describes a remarkable flat-worm, superficially like a Ligula , 
which he has found parasitic, chiefly in subdermal lymph-sinuses, in 
Hyla aurea. It has the form of a long and narrow, transversely ribbed 
white ribbon, and the largest was about two inches long and a tenth of 
an inch in breadth. The narrow segments of the body are very sharply 
defined in front ; no opening could be found and no vestige of hooks or 
suckers. There is no alimentary canal and the worm is probably, 
therefore, a Cestode. Its situation and the absence of reproductive 
organs show it to be a scolex. Only three genera of Cestodes are known 
to have solid, elongated scoleces — viz. Tetrarhynchus , Schistocephalus , 
and Ligula , but that of the first is cylindrical in form, and is un- 
segmented. 
An account is given of the appearances presented by sections of the 
worm ; a nervous system can be detected, but it is very indistinct ; the 
only internal organs that are well developed are the canals ; a main 
trunk of considerable size runs along each side ; numerous branches are 
given off, but not in any regular relation to the segments. 
Symbiosis of Echinococcus and Coccidia. :[ — Herr Lominsky found 
in the muscle of a ham a large number of nodules, roundish or oval in 
shape, and of a dirty grey or brownish colour. Most of the nodules were 
quite minute. The smallest consisted of a connective-tissue capsule with 
granular contents, in which the ovoid coccidia were very obvious. The 
larger ones contained as well as the coccidia an Echinococcus head with 
the characteristic hooklets. 
The author supposes the coccidia to be Coccidium oviforme, and that 
these have found their way into the nodules through the blood-vessels 
in the capsule. 
5. Incertae Sedis. 
Anatomy and Transformation of Tornaria.§ — Mr. T. H. Morgan 
comes to the conclusion that the larval Tornaria found on the coast of 
New England, and regarded by Agassiz as the young of Balanoglossus 
Kowalevskii, is not the young of that form. This explains the difficulty 
of Bateson who found direct or abbreviated development in that 
species. 
The free-swimming Tornaria undergoes many changes both in size 
and structure during its pelagic life ; the ciliated bands are not nearly 
so complicated in earlier as in later stages. As the larva increases in 
size, two posterior pairs of body-cavities appear, and a mass of cells is 
* Ann. and Mag. Nat. Hist., vii. (1891) pp. 534-5. 
f Proe. Linn. Soc. N.S.W., v. (1891) pp. 661-6 (1 p].). 
t Wratsch, 1890, No. 18. See Centralbl. f. Bakteriol. n. Parasitenk., ix. (1891) 
pp. 124-5. § John Hopkins Univ. Circ., x. (1891) pp. 94-6. 
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