388 ARTHUR DENDY. 



2. P. occidentalism Fletcher, with 15 (fifteen) pairs 

 of claw-bearing legs and no accessory tooth on the outer 

 blade of the jaw. Male with crural glands. Characteristic 

 of Western Australia. 



3. P. novEe-zealandige, Hutton, with 15 (fifteen) pairs 

 of claw-bearing legs and no accessory tooth on the outer 

 blade of the jaw. Male without crural glands. Characteristic 

 of New Zealand. 



4. P. S uteri, 2 Dandy, with 16 (sixteen) pairs of 

 claw -bearing legs and no accessory tooth on the outer blade 

 of the jaw. North Island of New Zealand. 



In the presence of crural glands in the male, Ooperipatus 

 is most closely related to the Australian species of Peripa- 

 toides, but in the structure of its eggs it stands nearer to 

 P. novse-zealandige. We may take P. Leuckartii and 

 P. novee-zealandiee as typical of the Australian and New 

 Zealand sections of their genus respectively. P. Leuckartii 

 is viviparous. The ovarian eggs, so far as my experience goes, 

 are comparatively small, and I can find no trace of a chorion, 

 but only a vitelline membrane. P. novce-zealandias, 

 though viviparous, has eggs nearly as large as those of 

 Ooperipatus, and according to Miss Sheldon, there is a 

 second membrane (chorion) outside the vitelline membrane. 

 Thus P. novse-zealandige in the structure of its eggs to 

 some extent resembles Ooperipatus, and this fact may help 

 us to solve the vexed question whether the oviparous or 

 viviparous habit is the more primitive. 



This question has been recently discussed by Willey (1), and 

 lie has come to the conclusion that "the oviparity of P. 

 oviparus, Dendy, is an acquired habit, and not in any way 

 to be confused with the primitive deposition of alecithal ova." 

 This may be very true, but I am inclined to think that even 

 if the structure of the eggs is secondary, yet the viviparous 

 habit must be regarded as still more recently acquired. 



P. novse-zealandise, with its large, heavily yolked eggs 



1 = P. Leuckartii, var. occicleiitalis, Fletcher (7). 



2 = P. iiovse-zealaiulice, var. Suteri, Dendy (13). 



