1-0 28 



Dorididae phauerobrancMatae. 

 Dor. phaiierobr. suetoriae. 



s. 



Êoniodorididae. 

 Comp. K. Bergh, System der nudibr. Gasteropoden, 1. c. 1S92. p. 1147 — 1157. 



Idaha. F. S. Lecckart. 



F. S. Letjckart, Br. animal, qnor. descript. 1S2S. p. 15. Fig. 2 a, b. 



B. Bergh, üb. die Gattung Idalia, Lettck. Aech. f. Natura. XLVII, I. 1881. p. 1-iO— 181. Tab. VI— VIII. 

 — 1. c. 1892. p. 1155—1156. 



Corpus vis depressum. dorso angustiori. podario latiori et eauda lanceolata pro- 

 ducto. >~otaeuni sat planum, margine nonnihil prominenti circumcirca continuo, papilli- 

 gero. Rhinophoria Lutramarginalia , sat magna, non retractilia; branchia postica, e foliis 

 simpliciter pinnatis arcu dispositis formata. Caput utrinque in tentaculum sat breve desi- 

 nens. Podarium latum, antice rotundatum, postice cauda applanata continuatum. 



Discus labialis aunulo angusto hamulorum confertorum armatus. Radula augusta, 

 rhachide nuda; pleurae dente lateral! majori hamiformi et externo lamelliformi. Inglu- 

 vies buccalis fortis fere sessilis. 



Glans penis bamulis armata; prostata magna. 



The genus is rather strongly marked off in the group of Goniodoridae {provided 

 with sucking apparatus/. Only a small number of species is known. 

 The new species mentioned below, belongs to the 



Subg. Idalia iproprie). 

 Notaeum medio papilligerum. 



Idalia plebeia, Bgh. n. sp. 

 PI. Ill, Figs. 15—19. 



I have before me four specimens of this form obtained near the coast of Lem Ngob. 



The colour of the specimens in spirit was light dirtily yellowish white; the 

 rhinophores and the point of the gill-leaves were black or brown black; spots of a similar 

 dark colour were also sometimes found here and there on the dorsal appendages. 



The length of the largest specimen was 11.5°™, that of the others about S™™. 



