118 Zoological Society. 



slate, a .d is involved in the sandstone above any high-water mark. 

 In support also of the land having been raised and not the sea de- 

 pressed, he referred to the submarine forests of Somersetshire, in the 

 prolongation of the same coast from Blue Anchor to the Parret ; and 

 argued that their position could not be accounted for by a subsidence 

 in the sea level, but by an unequal movement of the land. 



A communication by Mr. James de Carle Sowerby on his new genus 

 of fossil shells, Tropceum, was then read. 



This fossil is described by Mr. Sowerby as an involute chambered 

 shell with sinuated septa; the whorls free, sometimes very distant; 

 siphon in the external margin. The natural place of the genus is be- 

 tween Hamites and Scaphites, and the shells which may be grouped 

 with Tropaeum, have been hitherto ranked as Hamites, but have no 

 sudden bend which maybe compared to a hook. The species hitherto 

 found have been obtained from the gault and green sand. The 

 species ( Tropceum Bowerbankii) described in the paper was obtained 

 by Mr. Bowerbank in the Isle of Wight, and was found in the lower 

 green sand on the sduth side of the Island. 



ZOOLOGICAL SOCIETY. 

 Nov. 22, 1836 {continued). 

 The following observations on a species of Glaucus, referred to 

 the Glaucus hexapterygius, Cuvier, by George Bennett, Esq., F.L.S., 

 Corresponding Member of the Zoological Society, Surgeon and 

 Superintendent of the Australian Museum at Sydney, New South 

 Wales, were read. 



" On the 20th of April, 1835, during a voyage from England to 

 Sydney, New South Wales, in latitude 4° 26'*N., and longitude 19° 

 30' W., with light airs and calms prevailing at the time, about 3 

 p.m., a number of damaged and perfect specimens of the Glaucus 

 hexapterygius, Cuv., were caught in the towing net. On being im- 

 mediately removed from the net and placed in a glass of sea water, 

 they resumed their vital actions and floated about in the liquid ele- 

 ment, exhibiting a brilliancy of colour and peculiarity of form, 

 which did not fail to excite the admiration of the beholders. 



" The back of the animal, as well as the upper surface of the fin9 

 and digitated processes, and the upper portion of the head and tail, 

 was of a vivid purple colour, varying occasionally in its intensity ; 

 appearing brighter in colour when the animal was active or excited, 

 and deeper when remaining floating tranquilly upon the surface of 

 the water. The abdomen, and under surface of the fins, are of a 

 beautiful pearly white colour, appearing as if it had been enamelled. 

 The usual length of my specimens, measured from the extremity of 

 the head to the tail, when extended floating upon the surface of the 

 water, was If inches ; sometimes one or two lines more or less. 

 The body of the animal is subcylindrical, terminating in a tail, which 

 gradually becomes more slender towards the extremity, until it 

 finally terminates in a delicate point. The head is short, with very 

 small conical tentacula in pairs ; two superior, and two inferior ; 

 three (and in G. octopterygius, Cuv., four) branchial fins on each 



