CiiAP. I. SERIAL CONNECTION AMONG ANIMALS. 45 



GENERA -WITH ONLY TWO LEGS. 



No r('i)roscntativos arc known with fore leys only; but this structural combination occurs in the allied 

 family of the Cluilciilidids. The r('j)r('scntatives ivith hind legs only, present the following combinations: — 



Willi two toes : Scelotes, 1 sp., Cape Good Hope. 



With one toe: Propeditus, 1 sp., Cajie Good noi)e and New Holland; 



Ophiodes, 1 sj)., South America. 



Hysteropus, 1 sp., New Holland. 



JJdlis, 1 sp., New Holland. 



Dibamus, 1 sp., New Guinea. 



GENERA WITHOUT ANY LEGS. 



Anguis, 1 s])., Europe, Western Asia, Northern Africa. 

 Ophiomorus, 1 sp., Morea, Southern Russia, and Algiers. 

 Arontias, 1 sp.. Southern Africa, Cape Good Hope. 

 Typhlina, 1 sj)., Southern Africa, Cape Good Hojic. 



Wlio can look at this diagram, and not recognize in its arrangement the combi- 

 nations of thought? This is so obvious, that while considering it one might almost 

 overlook the fact, that while it was drawn up to classify animals preserved in the 

 Museum of the Jardin des Plantes in Paris, it is in reality inscribed in Nature by 

 these animals themselves, and is only read off when they are brought together, and 

 compared side by side. But it contains an important element for our dLscussion : 

 the series is not built up of equivalent representatives in its diiferent terms, some 

 combinations being richly endowed, others nimibering a few, or even a single genus, 

 and still others beuig altogether disregarded; such freedom indicates selection, and 

 n<jt the working of the law of necessity. 



And if from a contemplation of this remarkable series we turn our attention to 

 the indications relating to tlie geographical distribution of these so closely linked 

 genera, inscribed after their names, we i)erceive at once, that they are scattered all 

 over the globe, but not so that there could be any connection between the combina- 

 tions of their structural characters and their homes. The types without legs are 

 found in Europe, in Western Asia, in Northern Africa, and at the Cape of Good 

 Hope; the types with Iiiud legs only, atid with one single toe, at the Cape of 

 Good Hojx'. in Soutli America, New Holland, and New Guinea; those with two toes 

 at the Cape of (iood Hope only. Among the types witli fonr legs the origin of those 

 with but one toe to etich foot is miknown, those with one toe in the fore foot and 

 two in tlie hind foot are from South Africa, those with two toes in the fore foot and 

 one in tlie hind foot occur in the Philippine Islands, those with two toes to all four 

 feet in New Holland, those Avitli three toes to the hind feet and two to the fore feet 



