﻿50 MR. F. W 



ON SOME JAVAN DEEP-SEA LAGEN^ 



others the 



hyaline or semiopaque, very coarsely foraminated m some while m 

 pores are very fine or entirely wanting ; orifice central, circular, and more or less lipped ; 

 situated at the anterior extremity, and most commonly communicating with the interior 

 by means of an internal, slender, straight or flexed tuhe of very variable length, some- 

 fimes ending abruptly or becoming patulous at the free end. The base of the slieHis 

 very variable, presenting in some a widely rounded form, which even becomes flat or 

 dimpled in the centre, while in others it is furnished with a small mucro, or becomes 

 very peaked, insensibly passing into the apiculate varieties figured by Prof. Eeuss, and 

 between which there seems to be no line of demarcation. The anterior portion of the 

 shell is equally variable, in some being very bluntly rounded, while in others the reverse 



is the case. 

 Prof. Eeuss figures a form under the name L. emaciata, the only difference being in 



its more slender and elongated shape ; but this difference, together with that exhibited 

 by the square variety, L. inornata, of D'Orbigny, passes by so many intermediate grada- 

 tions into the egg-shaped and globular ones, that they cannot with propriety be 



separated. 



The amount of variation among this species is very remarkable ; and at first sight it 

 seems difficult to regard them all as belonging to the same species ; but like as the leayes 

 of the oak or the ivyvary greatly even on the same tree, and yet present unmistakahle 

 points of resemblance between one and another, so among the shells of this group, 

 though their contour is extremely variable, yet they present so great a family likeness, 

 both as regards shell-structure and absence of ornamentation, that it would be wrong to 

 separate them. 



These forms are, as a rule, symmetrical ; but in a few cases this uniformity of contour 



is impaired. These examples, however, are only adventitious. 



Occasionally one meets with shells having a suture-like mark on their shell-wall— the 

 shell having most probably been accidentally broken, and repaired by the contained 

 foraminifer (fig. 2). 



Lagena VULGARIS, Williamson, var. apiculata, Eeuss. (Eigs. 3-5.) 



The shells of this variety are in all respects simUar to those of the L. (Entosolem) 



globosa, saving that in these forms the base is more or less truncated or furnished with a 



mucro of very variable length. These varieties seem to form an intermediate ^^ 



between the the L, glohosa, and X. l(Bvi8 on the one hand and the Z. distoma on the 



other. Messrs. Parker and Eupert Jones unite under this name several forms, the base 



of which is provided with an aperture ; but though such shells are undoubtedly very 



closely alUed to the apiculate varieties, yet many forms occur in which this apiculatioQ 



of the base assumes a more caudate character, and forms a solid and sometimes curved 



basal appendage ; and therefore I am disposed to regard those with a true basal apertiii^ 



as belonging to the distomatous series, and to admit, under the name apictilafa, o' " 



those structures which, though produced at the base, are still imperforate. These 



however, pass so graduaUy from those with a rounded base that I question the propr 



of separating them from L. glohosa and L, Icevis, except for the sake of convenienc 



Occasionally one meets with abnormal growths, many of which are very remar 



,liells> 

 iety 



kablC' 



