The inference is almost irresistible that the law of gradual transformation through minute continuous change is by far the most universal; but many palaeontologists as well as zoologists and botanists hold a contrary opinion.
Such a young insect is a larva - a term used by zoologists for young animals generally that are decidedly unlike their parents.
Specimens were subsequently obtained from other parts of the neotropical region, and from South Africa and Australia, and the animal was variously assigned by the zoologists of the day to the Annelida and Myriapoda.
The Annelidan affinities are superficially indicated in so marked a manner by the thinness of the cuticle, the dermomuscular body-wall, the hollow appendages, that, as already stated, many of the earlier zoologists who examined Peripatus placed it among the segmented worms; and the discovery that there is some solid morphological basis for this determination constitutes one of the most interesting points of the recent work on the genus.
There are thus eight modifications of the horse-type at present existing, sufficiently distinct to be reckoned as species by most zoologists, and easily recognizable by their external characters.