1879.] NATURAL SCIENCES OF PHILADELPHIA. 81 



of the specimen examined 1 did not permit the determination of 

 the number of plates of the tongue and the posterior continuation 

 of the radnla. The median plates (PI. II. tig. 10a) with a greater 

 number of denticles, mostly with about 12-13; the lateral ones 

 with a rather produced outer limb (fig. 166, PI. I. figs. 16, 17), 

 the inner edge with a rather great number of (about 25-27) fine 

 denticles. 



As far as could be determined, a Penis-style existed, as it 

 seemed, of about the same form as in Fl. affinis (cf. 1. c. PI. XVI. 

 f. 3, 4). 



IV. HERMISSENDA, Bgh. 



Hermiwenda, Bgh., Beitr. zur Kenntn. den Aeolidiaden, vi. ; Verh. d. K. 

 K Zool.-bot. Ges. iu Wien. xxviii. 1878, p. 573. 



Corpus gracilins elongatum. Rhinophoria perfoliata, tentacula 

 elongata. Papillae dorsales in series obliquas et transversas con- 

 fertas areis prsesertim compluribus collatas dispositse. Poda- 

 rium antice angulis elongatis. 



Margo masticatorius mandibulse singula serie denticulorum 

 praeditus. Radula dentibus uniseriatis, denticulis elongatis prae- 

 ditis et cuspide infra serrulata. Penis inermis. 



In many respects this new genus seems to agree with the Phi- 

 dianse, as far as these are now known. 2 The general form of the 

 body, the rhinophoria and the tentacula are as in that genus, also 

 perhaps the disposition of the dorsal papillae. But the Hermis- 

 sendse differ in the rather produced angles of the front of the foot, 

 in the form of the teeth of the tongue, but especially in the want 

 of a hook on the penis. 



The body is rather elongated, slender The rhinophoria are 

 perfoliate, the tentacula long. The dorsal papillae seems to be 

 arranged in oblique and transverse rows, which form several more 

 or less separated groups. The angles of the front of the foot are 

 rather elongated. 



The cutting edge of the jaws has a single row of strong pointed 

 denticles. The teeth are in a single series ; each tooth with five 



1 The individual seemed to have been found dry in the glass and put in 

 new alcohol in such a state. Even the outer form could not be determined 

 before the specimen was softened. 



2 R. Bergh, Neue Beitr! zur Kenntniss der Aeolidiaden. I. Verh. d. K. 

 K. Zool.-bot. Ges. in Wien. xxiii. 1873, pp. 613-618. 



