•_'M 'NIK VOYAGE OF H.M.X CHALLENGER. 



during our run across, except at b depth of 50 fathoms; the lowest surface temperature 

 being 54°. Immediately previous to our arrival there had been few southerly winds. 

 afterwardl they blew with great regularity for a, fortnight, and if they extended any 

 distance southwest of the Cape colder water mighl naturally be looked for." 



PeripaHu, — During the stay at the Cape, one of the most important of the zoological 



discoveries of the voyage was made by Mr. Moseley. namely, that of the affinities of a 

 remarkable animal well known to naturalists under the name of PcrijKitiis, believed at 

 the time to be a peculiar and aberrant form of earthworm. The uncertainty and mis- 

 apprehension as to its affinities had arisen from the fact that it had never been examined 

 by any professed naturalist in the fresh condition, but was only known from specimens 

 preserved in spirit. Professor Moseley writes : — 



" The animal has the appearance of a black caterpillar, the largest specimens being more 

 than 8 inches in length, but the majority smaller. A pair of simple horn-like antenna' 

 projects from the head, which is provided with a single pair of small simple eyes. 

 Beneath the head is an opening surrounded by plicated lips, leading into a spare which 

 may be termed the pneoral cavity. Within this cavity lie a pair of muscular organs each 



Fio. 113.- Ptripatiu oepmvisj viewed from the dorsal inriioe (after Balfour). 



bearing two stout horny jaws behind which is situated the mouth. The animal has 

 seventeen pairs of short conical feet, provided each with a pair of hooked claws. The skin 

 is soft and flexible, and not provided with any chitinous rings. 



" The animal breathes air by means of tracheal tubes like those of insects, but these. 

 instead of opening to the exterior by a small number of apertures, — ' stigmata arranged at 

 the sides of the body in a regular manner as in all other animals provided with trachea;, — 

 are much less highly specialised. The apertures are in Peripatu* scattered more or 

 less irregularly over the greater pari of the surface of the skin. In the freshly killed 

 animal the trachea?, being distended with air, are readily seen, whereas in specimens 

 which have been steeped in spirit, and in which the air is absent, they are almost 

 invisible. 



'"The sexes are distincl in PeripOtus capensis. The males are much smaller and fewer 

 in number than the females. The females are viviparous, and the process of development 

 of the young shows that the horny jaws of the animal are the slightly modified claws of 



