THE DEVELOPMENT OP PETtlPATUS CAPENSIS. 451 
tions, which relate almost entirely to the early stages. Dr. 
Kennel has described his observations at very great length, but 
I do not think that his account of them can be regarded as en- 
tirely satisfactory. It is quite clear that Dr. Kennel has been 
hampered by want of material in the early stages, and by the 
great difficulty of the subject, and I therefore defer a detailed 
examination of his work to a later paper in the series of which 
this forms the first, by which time I hope that he will have been 
able to throw some more light upon certain points in the early 
development of the West Indian species, which are left some- 
what obscure in the first account in Semper’s ‘Arbeiten.’ On 
one point, however, there can be no doubt, viz. that the early 
stages in the development of the West Indian species are very 
different from those of the Cape species. Whether they are 
as different as Dr. Kennel makes out I am inclined to ques- 
tion, but that, as I have said, is a matter for further elucidation. 
Some of the. more important results of my observations on 
the development of Peripatus capensis, e. g. the derivation 
of the mouth and anus from the blastopore, the fate of the 
grooves in the cerebral ganglia, have already, some time ago, 
been published in my paper “ On the Origin of Metameric 
Segmentation ” (this Journal, 1884). 
My observations are nearly completed, and I have already 
(May of this year) communicated a preliminary account of 
them to the Royal Society. They will be published in full, I 
trust, in a series of papers in this Journal. 
The present paper is the first of the series, and relates 
almost entirely to the segmentation and general development 
of the embryo. I have deferred all discussion of the facts 
described to a more convenient opportunity in a later paper in 
the series. 
All the drawings in this paper, with the exception of figs. 
23 — 27, have been made by Mr. E. Wilson, of the Cambridge 
Scientific Instrument Company. They are very careful and 
accurate representations of the specimens, and I cannot suffi- 
ciently express my thanks to Mr. Wilson for the great trouble 
he has taken with them. 
