BRITISH MARINE TURBELLARIA. 243 



(Harvey) ; Falmouth (J. Cranoh, vide Johnston, 38) ; Jersey, Guernsey, 

 Herm (Koehler) ; two specimens oil Stoke Point, near Plymouth, 

 15 fins., on Diazona (J. T. Cunningham, MSS.) ; Plymouth Sound 

 (W. Garstang). 



Distribution. — Mediterranean, west coast of France, Scandinavia, 

 Denmark. 



66, PROSTHBCERiEUS argus (Quatrefages). 



1845. Proceros argus, Quatrefages (18). 



1859. ProstheceR/EUS argus, Schmarda, loc. cit. 



1868. EuRYLEPTA ARGUS, Keferstein (40). 



1884. Prosthecer^us ARGUS, Lang (54). 



1886. Proceros argus, Koehler (55). 



Length 6 — 10 mm. Body oval, bearing two short marginal tentacles 

 separated by the anterior extremity. Dorsal surface somewhat convex, 

 orange with white spots. The eyes are numerous : on each side of the 

 middle line extending behind the brain, and continued forwards to the 

 ventral faces of the tentacles. Thus the marginal, tentacular, and 

 cephalic groups are continuous. 



Habitat. — Between tide-marks at Grand Havre, Guernsey (Koehler). 

 Distribution. — St. Malo (Quatrefages, Keferstein). 



Genus 31. — Cycloporus, Lang (1884). 

 Dorsal surface papillose. Pharynx short. Cells of main-gut almost 

 filiform. About seven pairs of secondary branches. Uterine glands 

 correspond to the number of the latter. The peripheral gut-branches 

 open to the exterior through epithelial pores. Male pore close behind 

 the mouth. Copulatory organ beneath and behind the pharyngeal 

 sheath. Cephalic group of eyes not sharply defined. Tentacles small, 

 sometimes rudimentary. 



67. Cycloporus papillosus, Lang (54). PI. X, fig. 2. 



1880. Proceros tuberculatus, Schmidtlein, ' Mittheil. Zool. Stat. 



Stat. Neapel,' Bd. ii. 



1881. ,, ,, Lang, ibid., Bd. iii. 



Length 10 — 14 mm. Body elliptical with blunt extremities. In 

 front the antero-lateral margins are produced to a variable extent as a 



