ON THE UVll'AliOUS Si'EClES OF OXYCHOPilORA. 409 



Tasmania^ and New Zealand; distinguished by laying large, 

 heavily yolked eggs with a thick sculptured chorion, and by 

 the presence in the female of a conspicuous muscular ovi- 

 positor. 



2. The egg at the time of laying contains no recognisably 

 developed embryo, and development takes place afterwards 

 with extreme slowness. 



3. The oviparous habit is very ancient, dating back at 

 least to the Cretaceous epoch, as indicated by the geographi- 

 cal distribution of the species. The conclusions of Sedgwick 

 and Sclater as to the loss of yolk in the eggs of certain vivi- 

 parous species are thereby supported. 



4. Three species of Ooperipatus are at present known, 

 viz. 0. oviparus, 0. viridimaculatus, and 0. insignis. 

 Some slight doubt attaches to the last, because the eggs have 

 not yet been observed, but the females have the conspicuous 

 ovipositor. 



5. The genns Ooperipatus is very closely related to 

 Pocock's Peripatoidos, and may be regarded as represent- 

 ing an ancestral form from Avliich the viviparous Australasian 

 species are descended. 



6. Except as regards the egg-laying habit and structures 

 associated therewith, the genus Ooperipatus is, according 

 to the views of Bouvier, very far from primitive in its 

 characters, the number of walking legs being reduced to 

 fifteen or fourteen, the spinous pads being only three in 

 number, and the transverse ridges of the integument being- 

 interrupted in the mid-dorsal line by a narrow unpigmeuted 

 groove. 



7. There is no sufficient reason for supposing that Ooperi- 

 patus insignis, Dendy, is identical with Peripatus 

 Leuckartii, Sanger, which last name must be retained for 

 the common viviparous species of New South Wales. 



CuBisicuuRCU, N.Z. ; December, I'JOO. 



