PARASITES FREE WHILE YOUNG. 151 



from the head to the caudal region by means of their 

 oviferous tubes, which in certain seasons acquire a pale 

 green tint. 



The true Lerneans, such as the Lernea branchialis, a 

 species that was the earliest known upon the di£ferent 

 Gadidge, and which we have observed on the Callionyme 

 lyra, greatly resemble the Penellas, but their body and 

 their head are much twisted, and with the coils of tubes 

 which contain the eggs, you might take them for a ball 

 of thread. (Fig. 31.) 



The Sphyriones called Leister a have 

 also a most singular form, and a new 

 species has been recently observed on a 

 fish from the Straits of Magellan. The 

 Conchodermagracile lives on the branchiae Fig 31.— Lernea bran- 



CIllRllS, <ILL3.C11GCI to 



of the Ma'ia squinado, the sea-spider of the giiis of Morrhua 

 the Adi'iatic, and Mons. W. Salensky of 

 Charkow, found a copepod crustacean, the Spliseronella 

 Leuckarti, in the egg-pouch of an Amphito'e. The latter 

 parasite has very peculiar characters of conformation 

 and embryonic evolution. 



Among the molluscs, the Tunicates give lodging to 

 the greater number of lerneans ; in the cavity which is 

 before the mouth, and by which the food passes, some 

 are found which can scarcely be recognized, and which 

 remain there to smell out a feast. The Aplidium of the 

 coasts of Belgium gives lodging to some which are very 

 curious, and which we have named Enterocola fulgens, 

 on account of their colours. The Notopteropho7'us estab- 

 lishes itself on the body of the Phalliisia mamillaris, 

 and a certain number of these parasites are found on the 

 annelids. Professor Bars of Christiania, and Claparede 



