[ 757 ] 
XXII. On the Structure and Development of Peripatus capensis. By H. N. Moseley, 
M.A . , Naturalist to the ‘ Challenger ’ Expedition. Communicated by Professor 
Wyville Thomson, M.A., F.B.S., Ac.. Director of the Scientific Civilian Staff of 
the Expedition. 
Received April 9, — Read May 21, 1874. 
Introduction. 
At the outset I wish to express my obligations to Prof. Wyville Thomson, by whom 
this paper is communicated to the Royal Society. Prof. Thomson kindly examined a 
series of preparations of various structures in Peripatus , and gave me the benefit of 
his long experience in such matters, and especially confirmed my views as to the 
identity of the tracheae, which, of course, I had some hesitation at first in admitting as 
such, since they occurred in an animal in which, from what was at that time known 
concerning it, such structures were so little to be expected. Prof. Thomson further 
gave every encouragement to the prosecution of my further investigations on the 
subject. 
Peripatus has always been regarded as of such especial zoological interest that no 
apology is necessary for the present paper. Peripatus was naturally the first animal 
sought after by the naturalists of the ‘ Challenger ’ expedition on their arrival at the 
Cape of Good Hope, and I was lucky enough to find a considerable number of speci- 
mens on the very first occasion of searching for them. My intention had been only to 
try to keep the animals alive so as to obtain their eggs and watch their development, 
but on opening one large specimen I immediately recognized the presence of tracheae, 
and found the animal to be viviparous and full of far-advanced embryos. I therefore 
commenced as careful an examination of the structure and development of Peripatus as 
my available time during our stay at the Cape allowed ; and although the investigation 
is far from complete, the results embody so much that is novel and important that I 
consider it better to publish them now, leaving the gaps to be filled in by other 
observers, or by myself by further work at the subject during the Antarctic cruise of the 
‘ Challenger,’ should such work be then found practicable. 
Literature. 
No original papers on Peripatus are available to me here at the Cape of Good Hope, 
but from such text-books as Claus’s 4 Grundziige der Zoologie,’ Schmarda’s ‘ Zoologie,’ 
Gegenbaur’s ‘ Grundziige der vergleichenden Anatomie,’ tolerably complete information 
