368 Capt. F. W. Hutton on Peripatus novte-zealandige. 



form the mouth. By this time the anus has been formed by 

 the downward folding and growing together of the two poste- 

 rior lobes. The lobes of the cephalic ganglion remain free 

 until after birth. The joints and claws of the tarsi are not 

 developed until quite late. The eyes are developed before 

 the teeth. The young at birth are from '3 to '6 inch in 

 length. 



Systematic position. — The affinity oi Peripatus to the Tra- 

 cheata has been ably discussed by Mr. Moseley in his paper 

 already mentioned. To the evidence there brought forward 

 may now be added the salivary glands (which are much better 

 developed than in any of the Annelida), and possibly also the 

 moulting of the skin. But its affinities with the Annelida 

 are much stronger, as shown in the muscular, nervous, and 

 circulatory systems, the absence of biliary vessels, and in the 

 dorsal position of the trachege. The teeth are not homologous 

 with the mandibles of the Tracheata, but with the teeth of 

 the Annelida, and they closely resemble those oi Eunice. The 

 adductor muscles of the teeth have the same attachments as 

 those of the Annelida, and are widely different from those of 

 insects, in which they arise from the posterior part of the 

 head. The circulatory and nervous systems show most affi- 

 nity to some of the Tubicola. I do not regard the fact of P. 

 novce-zealandice being hermaphrodite as of much importance 

 in classification. 



Mr. Moseley has correctly said that Peripatus cannot be a 

 degraded Myriopod ; but neither can it be considered a direct 

 link between the Tracheata and the ringed worms. In all 

 probability it is a diverging branch from the main stem through 

 which the Tracheata were derived from the ringed worms. 

 It may be well placed in Professor Hackel's Protracheata ; but 

 the Protracheata must be put either as an order of the Anne- 

 lida, or as a distinct class of the Vermes. 



EXPLANATION OF PLATE XVII. 



Fig. 1. Section across anterior portion of Peripattis : a, ejaciilatory ducts ; 

 b, trachefe ; c, lateral vessels ; d, salivary glands ; e, nerve-cords ; 

 /, subcutaneous muscular layer ; g, stomacli. 



Fig. 2, Inner tooth. 



Fig. 3. Receptacle of ejaculatory vessel. 



Fig. 4. Ejaculatory gland. 



Fig. 5. Branch of dorsal tracheae. 



Fig. 6. Cephalic ganglion. 



Fig. 7. Portion of nerve-cord. 



Fig. 8. Generative organs : a, ovary ; b, testes ; c, oviducts ; d, nerve- 

 cords ; e, rectum ; /, vulva. 



Fig. 9. Ovum with germinal vesicle and spot (from ovary). 



