192 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Professor Perroncito elevates it into a new genus, to be called 

 Pseudo-rhahdiiis, and he gives a technical definition. The larvaB 

 are always killed at 48 'S** C. ; doliarine treated with hydrochloric 

 acid occasionally, but not always, was a fatal poison, 1 per cent, 

 solution of phenic acid was found to bo constantly poisonous, as were 

 other drugs, including an ethereal extract, of male fern, especially 

 when an alcoholic tincture of the same was added. The patient 

 already mentioned was supplied by the author with an alcoholic 

 liquor called fermet, and this was found to be mortal to the 

 parasite. 



Cercaria with Caudal Setae.* — Mr. J. W. Fewkes describes a 

 Cercaria, or larval Trematode, which differs considerably from any- 

 thing he has been able to find in any published figures. The 

 interesting feature is the Annelid character of the tail, a charac- 

 teristic which he considers may indicate some new relationship 

 between the Trematoda and the Annelida. 



The Cercaria is marine, and always found at or near the surface 

 of the water. Its length, when body and tail are extended, is about 

 y^^ inch. The body walls are very transparent. Its motion through 

 the water, as far as was observed, consists entirely of a "jerky" 

 motion, brought about by the powerful strokes of its very muscular 

 tail, a motion resembling very closely that of the nauplius of Balanus. 

 With moderate magnifying powers, the motions of the tail are so 

 rapid that they cannot be followed by the eye. 



The head is very variable, its shape being sometimes contracted 

 into a spherical ball, and at other times extended into an oval. At 

 the extremity is the mouth. The stomach occupies a large part of 

 the anterior central, jjart of the body, and from it there is continued 

 backward, a pair of blindly-ending vessels as in other Cercarise. The 

 most prominent structure of the body is a large medially placed 

 sucker. 



The tail is the most peculiar feature. Its general shape is hardly 

 characteristic, and it owes its interest to the bundles of setae arranged 

 on opposite sides at intervals along the whole length. These setae, 

 of which there are many in each bundle, are straight, inflexible, 

 and moved by muscles in the walls of the tail. Their resemblance 

 to the setae found in the segments of Annelids is very great. 



New Type of Turbellaria.| — W. A. Silliman describes a singular 

 worm which he found parasitic on a large green Nematoid, which was 

 apparently parasitic on Echinus splicera. 



The body of the animal is sublanceolate, 2*25 mm. long, with an 

 average breadth of 1-5 mm., and of a light brown colour. The 

 suckers and hooks so characteristic of ectoparasitic Trematoda are 

 wanting. 



The epiderm is formed of tolerably regular hexagonal ciliated 



* Amer. Jonrn. Sci., xxiii. (1882) pp. 134-5 (1 fig.), 

 t Comptes Rendus, xciii. (1881) pp. 1807-9. 



