vii RHODOPE VERANII 281 



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Appendage. 



Rhodope Veranii. 



This small animal (circ. 4 mm. in length) is long and sjiindle-shaped, and out- 

 wardly bilaterally symmetrical. Tlie body epithelium is ciliated all over. There 

 is a dermo-musoular tube, inside which, embedded in tlie connective tissue (paren- 

 chyma), are found numerous irregularly shaped calcareous particles. 



Alimentary Canal. — The mouth lies at the anterior end of this canal, and leads 

 into a wide buccal or cesophageal cavity, into the first part of which two acinose 

 salivary glands open. A radula and jaws are wanting. A narrow oesophagus con- 

 nects the cesophageal cavity with the tube-like mid-gut, which runs through the 

 whole length of the body. The midgut possesses a well-developed muscular wall, and 

 is continued anteriorly, above the point where the oesophagus enters it, in the form 

 of a diverticulum, which runs forward over the brain. There is no separate digestive 

 gland. The right side of the mid-gut gives rise to a short, thin, ciliated rectum, 

 which runs through the posterior third of the body, and opens through the anus to 

 the right. 



The nervous system consists of two pairs of ganglia lying so close together above 

 the oesophagus as almost to form one mass, and of one infra-oesophageal ganglion, 

 which lies somewhat asymmetrically to the left. The two ganglia of each of the 

 upper pairs are connected by transverse commissures, and the posterior dorsal pair 

 with the lower ganglion by two connectives which embrace the oesophagus. Two 

 lateral nerves which run backward are the most strongly developed. They arise out 

 of the posterior upper pair of ganglia, close to which lie a pair of eyes and a pair of 

 ciliated auditory vesicles, each of the latter containing an otolith. 



Genital Organs. — Rhodope is hermaphrodite. The gonads consist of about 20 

 follicles which lie ventrally in the median and posterior thirds of the body ; the 

 anterior follicles produce eggs and the posterior spermatozoa. , The ducts of all the 



