The Opisthobranchiata of South Africa. 79 



Dor. phanerobe. non suctorle s. Goniodoridid^. 

 R. Bergh, System, I.e., 1892, pp. 1147-1157. 



IDALIA, F. S. Leuckart. 



F. S. Leuckart, Br. animal, quor. descript. 1828, p. 15, fig. 2ab. 

 R. Bergh, tjb. die Gatt. Idalia, Leuck. Arch. f. Naturg. xlvii, 1, 1881, 

 pp. 140-181 ; taf. vi-viii. — System d. Nudibr. Gasterop., I.e., 1892, 

 pp. 1155-1156. 



Forma corporis sat alta. Notaeum proprium sat applanatum 

 cirrhis paucis seriatis vel omnino laeve, margine prominente cirri- 

 gero. Rhinophoria juxta-marginalia non retractilia. Branchia 

 postica, e foliis simpliciter pinnatis, in arcum dispositis formata. 

 Podarium sat latum, cauda applanata continuatum. 



Discus labialis annulo angusto hamulorum seriatim dispositorum 

 armatus vel utrinque lamina mandibulari elementis similibus formata. 

 Radula angusta ; rhachide nuda, pleuris dente majori hamiformi et 

 externo lamelliformi instructis. — Ingluvies buccalis fortis, fere 

 sessilis. 



Prostata magna ; glans penis hamulis armata. 



The form of the Idaliae is somewhat distinctive, not depressed. 

 The rather flat back proper shows some cirrhi set in series or is 

 quite smooth ; the margin projecting, somewhat turned up and 

 furnished with a series of cirrhi. The rhinophores stand apart 

 from each other anteriorly, not retractile, with perfoliated club. 

 The gill standing rather backwards, consisting of simple pinnate 

 leaves quite distinct from one another, set in the form of an arch. 

 The foot is rather large, continued in a short tail. — The bulbus 

 pharyngeus with a strong suctorial crop ; the lip disc of the bulbus 

 proper provided with an armature of densely set small hooks or with 

 mandibular plates. The radula is narrow ; the rhachis narrow, 

 naked ; the pleurae contain a very large compressed upright lateral 

 plate with plain or finely denticulated hook, and an outer small 

 lamelliform plate. — The prostata is rather large ; the glans penis 

 armed with hooks. 



The genus is divided into two subgenera : 



1. Idalia (proprie). 



Notaeum medium cirrhigerum. Discus labialis annulo hamigero 

 instructus. 



1. Id. elegans, Leuck. 



M. Atlantic, Mediterranean!;. 



