125 



rounded by a circular instead of a trigonal lip ; the Strong, trlgono- 

 cephttlus is placed by Rudolphi in the section c, ore nudo, while 

 the armature of the mouth, in tlie present species, is so remarkable, 

 as to induce me to regard it as the type of a new genus, which I pro- 

 pose to denominate Gtiathostoma*. 



. " Gen. Char. Co?'j3ms teres, elasticura, utrinque attenuatum. Caput 

 unilabiatum, labio circulari tumido integro ; os emissile, processibus 

 cornels maxilliformibus duobus lateralibus denticulatis. Genitale 

 masculum spiculum simplex, ad basin papillis circumdatum. 



" Sp. Gnath. spinigerum. Gnath., capite truncato, corporeseriebus 

 plurimis spinulorum armato. 



" The generic difference indicated by the external peculiarities of 

 the Entozoa above described, is confirmed by the internal anatomy, 

 which presents some peculiarities which appear not to have been 

 hitherto detected in the class Entozoa : I refer more particularly to 

 a distinct salivary apparatus, conformable to that which exists in the 

 Holothuria and other Echinodermata. This apparatus consists of four 

 elongated straight blind tubes, each about two lines in length, which 

 are jilaced at equal distances around the commencement of the ali- 

 mentary canal, having their smaller extremities directed forward, 

 and opening into the mouth, at the base of the lateral tridentate 

 processes, and their closed obtuse ends passing backwards into the ab- 

 dominal cavity. When examined with a lens of \ inch focus, the 

 parietes of these salivary tubes present very distinct oblique or spiral 

 decussating fibres ; their contents are semi-pellucid in the recent 

 worm, but become opake in spirit of wine. 



" I'he coexistence of these salivary glands with an oral apparatus 

 which is better adapted for trituration than any that has hitherto 

 been detected in the Entozoa, is conformable to the laws which re- 

 gulate the existence and condition of the salivary apparatus in higher 

 animals ; and is highly interesting on that account. The only allu- 

 sion which I can find to salivary organs in other Entozoa is in Clo- 

 quet' s ' Anatomie de rAsca7-ide Lomhricoide,' in which he considers the 

 thickened glandular parietes of the oesophagus to serve for an analo- 

 gous secretion. 



" The first portion of the alimentary canal or stomach, is about 3 

 lines in length ; it contains a milk-white substance, and is separated 

 by a well-marked constriction from the remaining poi'tion, which we 

 may regard as intestine : this is filled with a pulpy substance of an 

 amber colour, which grows deeper in tint as it approaches the anus. 

 The intestine enlarges slightly as it passes backward ; it is wide and 

 straight : is not tied down to the parietes of the body by mesenteric 

 filaments as in the Strongylus gigas, &c. ; its surface is irregular, and it 

 seems to contain a spiral tube or valve, but this appearance arises 

 from the nature of the internal surface of the intestinal tunics, which 

 is beset with large regular obtuse lozenge-shaped processes arranged 

 in alternate longitudinal rows. 



" The lateral lines of the body consist distinctly of two vessels, 



* yuxSoi; maxilla, aro/xx os. 



