26 
Spencer,* as upwards of twenty specimens were obtained between 
us. As so many keep enquiring, What is a Peripatus ? it may 
not be out of place to give a brief outline of the creature in this 
report, but for a full description I must refer you to Professor 
Sedgwick’s excellent works, “ A Monograph of the genus Peripa- 
tus ” and “ A Monograph of the Development of Peripatus 
capensis,” from which the following is extracted : — “ The genus 
Peripatus was established in the year 1826 by Guilding, who first 
obtained specimens from St. Vincent in the Antilles. He re- 
garded it as a Mollusc, being no doubt deceived by the slug-like 
appearance given by the antennae. Specimens were subsequently 
obtained from other parts of the Neo-Tropical Region, and from 
South Africa and Australia, and the animal was variously assigned 
by the Zoologists of the day to the Annelidse and Myripoda. Its 
true place in the system as a primitive member of the group 
Antliropoda was first established in 1874 by Moseley, f who dis- 
covered the tracheae. And there can be no doubt that Peripatus 
is an Antliropod, as it possesses features so characteristic of that 
group. Finally, the tracheae, though not characteristic of all 
the classes of ' Anthropoda, are found nowhere outside that 
group, thus constituting a very important reason for uniting 
Peripatus with it. Peripatus, therefore, is, zoologically, of extreme 
interest from the facts that, though in the main, Anthropodan, 
it possesses features which are possessed by no other Anthropod, 
and which connect it to the group to which the Anthropods are 
in the general plan of their organisation most closely related. It 
must therefore, according to our present lights, be regarded as a 
very primitive form, and this view is borne out by its extreme 
isolation, even at the present day. Peripatus stands absolutely 
alone as a kind of half-way animal between the Anthropoda and 
Annelida. There is no gradation in structure within the genus, 
and the species are limited in number.” 
Since the last clause was written by Sedgwick several zoolo- 
gists have divided them up into different genera as under; — 
Peripatus as the original name is retained for the Neo-Tropical 
species, Peripatoides and Ooperipatus for the Australasian species, 
Peripatopsis and Opisthopatus for the African, Paraperipatus for 
the New Britain, and Eoperipatus for the Malayan species. And 
I may say, taking them in the same order, the number of claw- 
bearing legs is very striking, the Neo-Tropical 28 to 43 pairs are 
*Description of a new species of I’eripatoides from Western Australia, by 
Baldwin Spencer, M.A., C.M.G., F.R.S., Professor of Biology in the University 
of Melbourne. Proceedings of the Royal Society of Victoria, Vol. xxi. (N.S.) 
pt. II., pages 420. 423. 
+ “ This is an animal of the very highest importance and antiquity, and I 
believe it to be a nearly related representative of the ancestor of all air-breathing 
Anthropoda, i. e . , of all Insects, Spiders, and Myriapods.”— H. N. Moseley. 
Proc. R.S., Lon., 1S74, Vol. xxii., pp. 344-35°. “On the Structure and Develop- 
ment of Peripatus capensis 
