462 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
y. Platyhelminthes. 
Helminthological Studies. — Prof. M. Stossich describes the numerous 
species which make up the genus Trichosoma* Rudolphi. Thirty-one 
forms with a smooth, unarmed penial cirrus are distinguished as 
Gymnothecee from sixteen Echinothecae in which the same structure 
bears spines or bristles, while one form ( Trichosoma crassicauda, Trichodes 
crassicauda according to Linstow) has no copulatory organ at all. 
Twenty-three species insufficiently defined bring up the total to seventy- 
one. Of these, twenty-three were found in mammals, thirty-nine in birds, 
three in reptiles, and the same number in amphibians and in fishes. 
In a seventh report on Tergestine helminthology, f Stossich notices 
over a score of parasitic worms, and figures Scolex polymorphus , Heterakis 
spumosa and fusiformis , Echinorhynchus lesiniformis and rubicundus , and 
four species of Distomum. 
In a third communication,^ he catalogues fifty-six parasites from a 
collection made by Dr. A. P. Ninni, and briefly describes Distomum 
crassiusculum, Tsenia emberizorum , and Heterakis compar. 
The Skin of Ectoparasitic Trematodes.§ — Herr M. Braun con- 
cludes from observations on Polystomum integerrimum, Nitzschia 
( Tristomum ) elongata , and Epibdella hippoglossi, that the outer layer 
on the body of ectoparasitic Trematodes is a modified epithelium, which 
in certain conditions of altered function, e. g. in forming the hooks of 
Polystomum or the lateral suctorial pits of Nitzschia , retains its original 
epithelial character. 
Anatomy of Amphiptyches urna.|| — Prof. W. Baldwin Spencer gives 
an account of the structure of this parasite. It was first observed by 
Wagener in Chimsera monstrosa , and Prof. Spencer has found it in the 
southern representative of that fish — Callorhynchus autarcticus. When 
alive it is of a creamy white colour, and the sides of the body and one 
end are crenate ; this end the author, in opposition to Wagener, believes 
to be the anterior, and not the posterior. The opposite end of the body 
is characterized by a rosette of folds, and is pierced in the centre by a 
small tubular space which leads into the body ; this space soon turns 
dorsalwards and opens to the exterior by a slight proboscis-like structure ; 
the proboscis is capable of protrusion or retraction. It is difficult to 
assign any function to this curious structure, or to homologize it with 
anything present in other Cestodes, or, in fact, in other Vermes. 
The most prominent feature of the body- wall is the presence of very 
distinct and numerous spines, which are generally distributed over the 
body-surface. The spines are somewhat elongate and are each composed 
of concentric layers of a transparent material. The epidermis consists 
of long, thin, columnar cells which pass internally into a layer of 
apparently homogeneous material ; some of the cells are glandular, and 
they possibly secrete a sticky material which enables the parasite to 
adhere to the walls of the alimentary canal of its host. 
* Boll. Soc. Adriat. Sci. Nat., xii. (1890) pp. 3-38. 
t T. c., pp. 39-47 (1 pi.). X T. c., pp. 49-56. 
§ Centralbl. f. Bakteriol. u. Parasitenk., vii. (1890) pp. 594-7. 
(I Trans. Roy. Soc. Victoria, i. (1890) pp. 138-51 (3 pis.). 
