REPORT ON THE GENUS ORBITOLITES. 3 



is a humble representative of the type of structure which attains its full development in 

 the MarginoiMra of Quoy and Gaimard, does not seem to have occurred to him ; and it 

 is evident, from his description of the latter, that in that type also he failed to recognise 

 the true marginal pores, — what he supposed to be such being incomplete chamberlets 

 left open in the frilled edges of the abnormal specimens (resembling those figured in 

 PI. VII.) which represent this genus in the Paris Museum. 



Notwithstanding the special attention which M. d'Orbigny was giving to the minute 

 shells now ranked as Foraminifera, he does not seem, when he presented in 1825 to 

 the Academic des Sciences his Tableau Methodique of that group (which he then 

 ranked as a sub-class of Cephalopoda), to have had the least idea that Orhitolites and 

 Marginopora should have a place in it ; and no mention is made of either in the 

 systematic arrangements published by him in 1844 (Diet. Univ. d'Hist. Nat., torn, v.) 

 and in 1846 (Foram. Foss. de Vienne), in both of which he fully accepted the view of 

 the Rhizopodal character of the animals that form Foraminiferal shells, which had been 

 promulgated by M. Dujardin in 1835. 



Dujardin's doctrine, however, was strongly opposed by Prof. Ehrenberg ; who, in 

 1838, announced to the Berlin Academy^ his conclusion — avowedly based on observation 

 of certain forms of these animals in the living state — that the true place of the Foraminifera 

 in the animal kingdom is in the class Briozoa, first constituted by him on the basis 

 of what were then known as " Ciliobrachiate Polypes," viz., Fhtstrce, IlalcyoneUce, &c. 

 In this group he correctly assigned a j^lfice to the genus LuniiJitcs ; and it seems to have 

 been from the superficial resemblance which (as both Lamarck and De Blainville had 

 noticed) is borne to the calcareous disk of Lumdites by Orhitolites, that he associated 

 the latter with the former in his Order Pohjthalamia , Family Asterodiscina. Having 

 some years previously visited the Red Sea, for the purpose of zoological exploration. Prof. 

 Ehrenberg had brought thence two kinds of small calcareous disks, which he saw to pos- 

 sess similar general characters ; upon one of these he conferred the generic name Sorites, 

 and upon the other Amphisorus ; and he erected these into the Family Soritidce, which 

 he placed next to the Asterodiscina. It is perfectly clear, from his descriptions and 

 figures of these disks, that Ehrenberg's Sorites is identical with Lamarck's Orhitolites 

 marginalis, tlie small recent type inhabiting the Mediterranean ; and that his, Amphisorus 

 is so closely allied to this, that its diff'erence is not more than specific. But he was so 

 completely carried away by his preconceived ideas, as not only to describe the entirely 

 closed cells of the surface of these disks (which are only open in dead and abraded 

 specimens) as covered with a moveable operculum, which shuts their orifices when 

 their animals are retracted, but actually to figure an eight-armed Bryozoon as issuing from 

 one of them. 



1 Ueber noch jetzt lebenile Thierarten der Kreideljildimg, und den Orgaiiismus der Polythalamien. Ahhancl- 

 ungen der hiinirjl. Alcad. der TFiasenschaften zu Berlin, 1839, p. Rl. 



