Being Transactions of the S. Afr. Phil Society. Vol. XVII. 89 



cnidogenae nullac ; anus ut plurimum dorsalis, posticus medianus ; 

 rhinophoria ut plurimum perfoliata, tentacula brevia ; margo anterior 

 podarii angulis vix prominentibus. 



Mandibulae foi'tissimae, margo masticatorius applanatus, aut 

 edentulus aut denticulis crassioribus armatus. Eadula ut plurimum 

 lata et multiseriata ; dentes, mediani sicut laterales, elongati hamati 

 non denticulati. 



Penis inermis. 



The Janidse form a very distinct group. The anus lies mostly 

 dorsal, far backwards and median. But their most essential 

 character is the possession of colossal mandibles, the flat mastica- 

 tory edge of which is even or bears very strong denticles. The 

 lingual teeth, median as well as lateral, are elongate, never 

 denticulate. 



The family contains a few genera, mostly very distinct. 



I. Janus, Verany. 



E. Bergh., Beitr., 1. I.e., xxiii., 1874, pp. 597-605 ; vii.. I.e., xxxii., 



1882,. pp. 64-66. 

 Vayssi6re, I.e., 1888, pp. 29-32. 



Ehinophoria perfoliata, crista interrhinophorialis ; anus dorsalis. 

 Margo masticatorius latus dentatus. Eadula multiseriata. 



1. /. eristatus (delle Chiaje). 



M. Atlantic., Mediterr. 



2. J. ? sanguineus, Angas. 



M. Pacific. 



II. Janolus, Bgh. 



E. Bergh, Eep. on the Nudibr., I.e., 1884, pp. 18-23.— Malacolog. 



Unters., vi., 1. 1904, p. 6. 

 Ehinophoria perfoliata, crista interrhinophorialis ; anus dorsalis. 

 Margo masticatorius latus non dentatus. Eadula multiseriata. 



1. J. hyalinus (A. et H.), B. 



M. Atlantic. 



2. /. Aicstralis, B. 



M. Pacific7im. 



3. /. ccBruleo-pictus, Cockerell et Eliot.* 



M. Californ. 



4. /. Capensis, B. n. sp. 



M. Capense. 



* " Notes on Californian Nudibranchs," Journ. of Malacology, xii., 1905, p. 48, 

 pi. viii., figs. 12-16, 



