380 



CH.ETOPODA. 



iN ii])crture are two hook-shaped papilla?. The larva: are in part parasitic in the 

 Cydippidce. Alrlopa, Cunt nti nil Delle Ch., Naples. 



Fam. Tomopteridae (Grymnwnjia'). Head well marked, two eyes, ' bifid 

 prasstomium, and four tentacles, of which two in many species are only present 

 in the young. The mouth segment has two long tentacular cirri which are 

 supported by a strong internal seta. The mouth is without proboscis and 

 jaws. The segments are provided with large bi-lobed parapodia without seta?.. 

 ToiHOjiti-rix xcoliyeHflra Kef., Mediterranean. T. <tixri/(ir>nis Esch., northern 

 seas, Heligoland. 



The genus Myzostoma F, 8. Lkt., a small group of hermaphrodite worms 

 whose affinities are doubtful and disputed, may be placed here. They are 



small, disc-shaped animals, 

 parasitic on Conn/tula. 

 They possess a soft and 

 ciliated skin, four pairs of 

 laterally placed suckers on 

 the ventral surface, and a 

 protrusible proboscis fur- 

 nished with papillse at 

 their anterior end. also a 

 branched alimentary canal 

 which opens at the posterior 

 end of the body. On the 

 sides of the body are rive 

 pairs of short parapodia, of 

 which each one bears a hook 

 (with one to three supple- 

 mentary hooks) as well as 

 supporting setre. As a rule, 

 , double as many cirri or 



short wart-like protube- 

 rances- are found on the 

 margin of the body. M. 

 ///(ihnim, clrriferum F. S. 

 Lkt. 



D Sub-order 2. Seden- 



'Ov taria = Tubicolse. * 



Fra. 30R.-SpirorM> laris (after Claparede). a, The With indistinctly S6pa- 



aniiual removed from its tube, strongly magnified; rated head and short 

 b, tube ; T, tentacles ; Et, brood-pouch with oper- 



culum ; Dr, glands, Or, ova ; Oe, oesophagus ; 3f, usually not protl'USlble 



stomach ; A intestine. proboscis, without jaws. 



The branchire may be entirely absent and in many cases are 

 confined to the two or three anterior segments following the 

 head. In exceptional cases they are placed on the dorsal part 

 of the middle of the body (Arenicolidw). As a rule, however, 

 they are represented by numerous filiform tentacles and ten- 



* E. Claparede, " Kecherches sur la structure des Annelides sedentaires," 

 (?enve, 1873. 



a 



