Cheeseman. — On Chromodoris. 137 



Art. XXX. — On a New Specie* of OhromodoriB. 



By T.F. Cheeseman, F.L.S. 



[Rend before the Auckland Institute, 1st June, 1885.] 



A few months ago, Captain Farquliar, of the steamer Clansman, 

 v< iv kindly brought to the Auckland Museum a living speci- 

 men of an exceedingly handsome Nudibranch, found by him on 

 the rocks at Whangaroa Harbour. Since then I have also 

 had specimens in alcohol, of the same species, sent to me 

 from Whangarei Heads. It proves to be undescribed, and to 

 belong to the genus Chromodoris, of which only one species 

 was previously known to inhabit our coasts — viz., C. aureo- 

 marginata*, a pretty little animal occasionally seen in Auckland 

 Harbour. Captain Farquhar's species is larger, and much more 

 brightly and vividly coloured. The following is a description : — 



Chromodoris amcena, n. sp. Body 1| to 2 inches long, linear- 

 oblong, rounded in front, pointed behind, back slightly convex. 

 Mantle smaller than the foot, quite smooth and even, pale 

 pinkish or purplish lilac, with a central row of large bright 

 orange oblong spots, and occasionally a few lateral ones, margin 

 pale creamy or yellowish white. Dorsal tentacles (rhinophores) 

 clavate, completely retractile within slightly raised sheaths ; 

 upper part arched backwards, laminate, laminae from 24 to 25. 

 Branchiae completely retractile, 10 in number, connected at the 

 base, small, erect, linear, simply pinnate. Both tentacles and 

 branchiae are a bright magenta colour. Oral tentacles free, 

 small, conical. Foot paler than the mantle, the sides and 

 extremity with an irregular double row of roundish bright 

 orange spots, considerably longer than the mantle ; sole, pale 

 flesh-colour. Odontophore of about 65 rows of teeth ; central 

 tooth small, laterals from 60 to 70 on each side. Mantle 

 spicules apparently wanting. Ova deposited in a spiral coil of 

 four turns. 



Captain Farquhar's specimen lived in confinement for more 

 than a month, during this period depositing its ova. It was 

 lively and active in its habits, and was fond of floating in a 

 reversed position just under the surface of the water, as is the 

 case with many of the Xudibranchs. Its graceful form and 

 bright colours render it one of the handsomest species yet dis- 

 covered in New Zealand. 



" Trans. N.Z. Inst.," vol. xiii., p. 223. 



