74 ZOOLOGISCHE MEDEDEELINGEN — DEEL VI. 



the genera „weil vom zweiâstigen Ruder durch Yerkümmerung des oberen 

 Astes zum tuberkelartigen Vorsprung ein allmâhlicher Übergang zum 

 einfachen Ruder stattfindet." Therefore I used in the first place the 

 number of tentacular cirri to distinguish the genera and in the second 

 place the number of cephalic appendages; thus 15 genera could be 

 distinguished, which can easily be recognized by the following key : 



1 pair of tenta- / Unpaired antenna absent Pilargis St. Jos. 



cular cirri on < Unpaired antenna i Parapodium uniramous Orseis Ehl. 



each side ( present ! „ biramous with dorsal hook shaped bristle. AncistrosylHs Mc Int. 



2, 3 or 4 pairs' 



Unpaired antenna absent ; proboscis with papillae on its anterior 



margin and two ventral ridges Casialia Sav. 



of tentacular 



cirri on each 



side 



3 pairs of tenta- 

 cular cirri on 

 each side 



Unpaired antenna j parapodia uniramous Syllidia Qfgs. 



absent \ „ biramous Lamproderma Gr. 



!anal plate present Microphthalmus Mecz. 

 , ( proboscis armed Tnnv.'la Ehl. 

 no anal | x 

 , , j proboscis j parapodia faintly biramous . . . Podurlce Ehl. 



unarmed ( „ distinctly biramous . Ophiodromus Sars 

 Unpaired antenna absent : Periloea Ehl. 



7 tentacular 



cirri (3 and 



two pairs) on 



each side 



„ , [ Unpaired antenna ( palps distinct Dal It on si ell a Mc Int. 



4 pairs of ten- 1 1 



tacular cirri on 

 each side 



absent ( no palps visible Hesione Sav. 



Unpaired antenna ( proboscis armed Leocrates Kbg. 



present | „ with papillae on its anterior margin. . . . Gyptis Mar. & Bobr, 



Genus Pilargis Saint- Joseph. 

 (Phronia Webst.). 



Body long, with numerous segments. Cephalic lobe reduced, heart- 

 shaped, with two antennae and two palps. Eyes absent. Proboscis unarmed. 

 A single pair of tentacular cirri on each side. Parapodia faintly biramous, 

 without dorsal setae. 



A. Tentacular cirri and dorsal cirri of the first setigerous segment much 

 larger than the succeeding ones. 



tardigrada Webst. Trans. Albany Institute, Yol. IX, 1879 p. 68, 

 PL XI, figs. 158—163. Coast of Virginia. 



B. Tentacular cirri and dorsal cirri of the first setigerous segment little 

 larger than the succeeding ones. 



verrucosa St. Jos. Ann. Sc. Natur. (8e Sér.) Yol. X, 1899, p. 175, 

 PI. VI, figs. 10—17. Fauvel, Bull. Soc. Zool. do France,^ Yol. 45, 

 p. 208, fig. 1, a — e. Coast of France (Brest and Arcachon). 



