412 ENTOZOA. 



four feet in length. It remains buried in the sand, and, it is 

 said, attacks the Anomiae, which it sucks in their shell *. 

 In the vicinity of Nemertes should probably be placed the 



TuBULARiA, Renieri, 

 Equally large and extremely elongated, but furnished with a small 

 raouth opening under the anterior extremity. 



Ophiocephalus, Quoy, Gaym., 

 With the same form, but the extremity of the mouth cleft. 



Cerebratula, Renieri, 

 Which seems only to differ in the greater shortness of the body f. 



ORDER II. 



PARENCHYMATA. 



The second order of the Entozoa comprises those species in which 

 the body is filled with a cellular substance, or even with a continuous 

 parenchyma, the only alimentary organ it contains being ramified 

 canals, which distribute nourishment to its different points, and which, 

 in most of them, originate from suckers visible externally. The 

 ovaries are also enveloped in this parenchyma or that cellulosity. 

 There is no abdominal cavity, nor intestine properly so called ; the 

 anus is wanting, and if we except some equivocal vestiges in the first 

 families, there is nothing to be found which bears a resemblance to 

 nerves. 



AVe may divide this order into four families 



FAMILY I. 



ACANTHOCEPHALA. 



The Parenchymata of this family attach themselves to the intes- 

 tines by a prominence armed with recurved spines, which also appears 

 to act as a proboscis. They form the single genus 



ECHINORHYNCHUS, Gm., 

 Where the body is round, sometimes elongated, and sometimes in the 

 form of a sac, provided anteriorly with a prominence in the form of 



• For this singular worm, which is mentioned by Borlasse only, I am indebted to 

 M. Dumeril, who found it near Brest. It is the genus Borlasia of Oken ; M. 

 Sowerby had previously called it Lineus. 



t We have neither seen the Tubularia nor Cerebratula. The names of Tubularia 

 and Ophiocephalus, being already applied to other genera, cannot subsist. 



