298 RHOPALOMENIA. 



Salivary glands 2 ; penial exciting organs two or none. Length 6- 

 60 mill., 6 to 25 times the breadth. 



This genus is evidently composed of somewhat heterogeneous 

 elements, which, however, share the peculiar shape and arrangement 

 of spicules described above, and the same mode of existence, differ- 

 ing in both from the northern genus Proneomenia. 



Thiele (Archiv Wiss. Zool., Iviii, p. 273) proposes to restrict Rho- 

 palomenia to the species aglaophenim and eisigi, and relegate vagans, 

 desiderata, gorgonophila and acuminata to Proneomenia. I have, 

 however, considered it advisable to leave the group within the lim- 

 its fixed by Simroth, except that sopita is removed, as it obviously 

 differs sufficiently to form another genus. 



Key to Species of Rhopalomenia. 



Cuticle Exciting Salivary Rfldnla G : lls Length 

 papillae organs glands index 



one-celled 2 present none 25 gorgonophila. 



n j f 2 2 present 6 vaqans. 



many-celled | Q g r*^ none 6 d / siderata . 



( none none 13 aglaophenice. 



Of these species, the first is separated widely from the others by 

 its peculiar cuticle-papillae. The West Indian R. acuminata is still 

 too little known to be included in the table. 



R. GORGONOPHILA (Kowalevski). PI. 44, figs. 30, 31, 32. 



Elongated, cylindrical, winding around Gorgonia stems, upon 

 which it is parasitic. Length 60 mill. 



Algeria and Provence. 



Neomenia gorgonophila KOWAL., Bull. Roy. Soc. Friends of Nat. 

 Science, etc., 1881 (Russian) ; Zool. Auzeiger, iii, p. 190. Proneo- 

 menia gorgonophila KOWAL. & MARION, Mem. Mus. Hist. Nat. Mar- 

 seilles, III, p. 75, pi. 7, f. 18-21. Rhopalomenia gorgonophila SIM- 

 ROTH, Bronn's Thier-Reichs, p. 230, pi. 4. figs. 2-4. 



Fig. 30 represents the animal in its natural position. Fig. 32 

 section showing foot-groove and foot. Fig. 31 section through the 

 skin, showing epithelium above, below it the peculiar club-shaped 

 inter-cuticular papillae, and lower the horizontal spicules, with a 

 layer of circular muscle beneath. 



