298 VENOMS 
ing the cannelures and the skin, which is distended to allow it to 
pass. 
Towards the base of the spine, the edges of the cannelure are 
united, and form a hollow, bony cone, the walls of which are lined 
with the cells that secrete the toxic fluid. 
Greater Weevers are 
usually from 12 to 30 cm. in 
length, and of a reddish or 
yellowish-grey colour, with 
blue or violet spots. They 
are caught in trawls and are 
fairly common on sandy 
bottoms. In the month of 
June they approach the shore 
for the purpose of spawning. 
The venom of the Weever 
has formed the subject of 
interesting studies by Giin- 
ther, Gressin,) PBottard, 
Fig. 108.—A, Operculum and opercular spine rie Raise no _ ee 
of the Lesser Weever (Trachinus vipera) ; ar, Phisalix, and more recently 
articular surface of the operculum ; c. op, body by Kobert® and A. Briot.! 
of the opercular spine; c.an, canal of the ; ; 
spine ; z, space occupied by the poison-gland. In order to procure suffi- 
, Spine belonging to the first dorsal fin; c. an, : ne à 
efferent poison-canal in the spine. cient quantities of it for ex- 
perimental purposes, Briot 
cuts off the venomous spines and the surrounding tissue with a pair 
of scissors; he then pounds the whole in a mortar, and mixes the 
pulp with pure glycerine. After filtration through paper, a toxic 
solution is obtained, which does not deteriorate by keeping, and is 
neutral to litmus. 
' Thèse Paris, 1884. 
* Bulletin du Muséum d'histoire naturelle, 1899. 
*“ Giftfische und Fischgifte,” Vorträge im Rostocker Fischerverein, 1902, and 
Die medizinische Wochenschrift, 1902. 
* Comptes rendus de la Société de Biologie, October 25 and November 8, 1902, 
and June 21, 1904 ; Journal de Physiologie, March, 1903. 
