XV. ON CERTAIN POINTS IN THE ANATOMY OF 

 PERIPATUS CAPENSIS'. 



THE discovery by Mr Moseley 2 of a tracheal system in Peri- 

 patus must be reckoned as one of the most interesting results 

 obtained by the naturalists of the " Challenger." The discovery 

 clearly proves that the genus Peripatus, which is widely dis- 

 tributed over the globe, is the persisting remnant of what was 

 probably a large group of forms, from which the present tracheate 

 Arthropoda are descended. 



The affinities of Peripatus render any further light on its 

 anatomy a matter of some interest ; and through the kindness 

 of Mr Moseley I have had an opportunity of making investiga- 

 tions on some well preserved examples of Peripatus capensis, 

 a few of the results of which I propose to lay before the Society. 



I shall confine my observations to three organs, (i) The 

 segmental organs, (2) the nervous system, (3) the so-called fat 

 bodies of Mr Moseley. 



In all the segments of the body, with the exception of the 

 first two or three postoral ones, there are present glandular 

 bodies, apparently equivalent to the segmental organs of An- 

 nelids. 



These organs have not completely escaped the attention of 

 previous observers. The anterior of them were noticed by 

 Grube 3 , but their relations were not made out. By Saenger 4 , as 

 I gather from Leuckart's Bericht for the years 1868 9, these 

 structures were also noticed, and they were interpreted as seg- 



1 From the Proceedings of the Cambridge Philosophical Society, Vol. in. 1879. 



2 "On the Structure and Development of Peripatiis Capensis" Phil. Trans.. 

 Vol. CLXIV. 1874. 



3 " Bau von Perip. Edwardsii" Archiv f. Atiat. u. Phys. 1853. 



4 Moskauer Nattirforscher Sammlung, Abth. Zool. 1869. 



