RHOPALOMENIA. 299 



R. VAGANS (Kowalewski & Marion). PI. 44, figs. 37, 38, 39. 



Cylindrical, both ends similarly roundly-pointed. Cuticle homo- 

 geneous. Free living upon Zostera ; 6 mill, long, 6 or 7 times the 

 diameter. 



Gulf of Marseilles. 



Proneomenia vagans Kow. & MAR., Ann. Mus. d'Hist. Nat. Mar- 

 seilles, iii, p. 29, pi. 3, 4, 5, 1887. THIELE, Zeitsch. Wisseusch. Zool., 

 Iviii, p. 258, pi. 15, f. 95-107. Rhopalomenia vagans SIMROTH, I. c., 

 p. 230, pi. 5, figs. 1-7. 



Fig. 38 shows the animal magnified 30 diameters, with the dorsal 

 integument removed by the microtome, showing the intestinal coeca 

 and (by transparence) the longitudinal salivary glands lying under 

 them. Fig 39, ventral view of the hind end. Fig. 37, a spicule, 

 x 510. 



R. DESIDERATA (Kowalewski & Marion). 



Body cylindrical, rounded at the two ends, 10 mill, long ; cuti- 

 cular layer relatively not very thick, formed of distinct layers, ir- 

 regularly superimposed ; cutaneous papillae small, several-celled, for 

 the most part not extending near the outer surface. Spicules all 

 acicular, perceptibly curved. Radula well developed. 



Marseilles, on Posidonia. 



Proneomenia desiderata Kow. & MAR., 1. c., p. 59, pi. 5, f. 28-34. 

 PRUVOT, Arch. Zool. Exper. et Gener. (2), ix, p. 732Rhopalo- 

 menia desiderata SIMROTH, I. c., p. 230, pi. 4, fig. 5, 6. 



R. AGLAOPHENI^; (Kowalewski & Marion). PI. 45, figs. 46-56. 



Elongated, somewhat narrowed behind. Cuticle homogeneous. 

 Frontal sense-tubercle retracted into the mouth cavity. Length 32 

 mill. Although the radula may be lacking, its supporting mem- 

 brane and sheath remain. Parasitic. 



Marseilles, Banyuls, Naples and Plymouth on Aglaophenia. 



Proneomenia aglaophenice Kow. & MAR., Ann. Mus. d'Hist. Nat. 

 Marseille, iii, p. 65, pi. 6, 7. PRUVOT, Arch. Zool. Exper. (2), ix, 

 pp. 720, 732, 760 ; Comptes Rendus, cxiv, p. 1211 (embryology). 

 Ehopalomenia aglaophenias SIMROTH in Bronn,p.230, pi. 4, f. 7-16. 

 THIELE, Zeitsch. Wiss. Zool., Iviii, p. 265, pi. 15, f. 108-114 ; pi. 

 16, f. 115-122. GARSTANG, Proc. Mai. Soc. Lond.,ii, p. 124, pi. 10, 

 f. 3. 



