152 ANIMAL PARASITES ANB MESSMATES. 



have carefully described them; and the latter saw on 

 the Spirographis Spallanzani of the bay of Naples, a 

 female which he called Sahelliphilus Sarsii. The genera 

 Selius, Silenium, Terehellicola, Chonephilus, Sabellacheres, 

 Nereicola, &c. infest all the annelids ; the Eurysilenium 

 truncatum lives on the Polinoe impar, the Melinnacheres 

 ergasilo'ides on the Melinna cristata. 



The echinodermata and the polyps are not free from 

 lerneans ; thus the Asterochoeres Lilljeborgii fixes itself 

 on the Echinaster sanguinolentus, and we have found a 

 very beautiful species in Brittany on an Ophiurus ; the 

 Lodmippa rubra, allied to the Chondr acanthi, lives upon 

 the Pennatula rubra, the Laura Girardise, according to 

 Mons, Lacaze Duthiers, feeds on an Antipathes. A 

 Loemippus (Proteus) lodges in the cavity of the body of 

 the Lobiolaria digitata of Delle Chiaie ; and lastly, the 

 Enalcyonium rubicundum is sheltered by the Alcyonium 

 digitatum. 



There are certain worms which are free when young, 

 and only become parasites at a later period of their 

 evolution. We will give a few examples. 



The Medina, or Guinea worm {Filaria Medmensis, 

 dracuncidus) (Fig. 32), is the terror of travellers who visit 

 the coast of Guinea ; it is common, not only on the western 

 coast of Africa, but also in many other parts of this vast 

 continent, and has been recently found in Turkistan and 

 South Carolina (Mitchell). It was formerly thought that 

 this Filaria could introduce itself directly through the skin 

 as a microscopic embryo ; but Mons. Fedschenko, after 

 some observations made on the spot, and corroborated ex- 

 perimentally afterwards by Leuckart, is of opinion that this 

 worm is transmitted by means of the Cyclops, a little 



