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MR. F. W. O. RYMER JONES ON SOME JAVAN DEEP-SEA LAGEN^ 



65 



portion the shell- waUs contract for a short distance, hut soon hulge out again, and form 

 a second flask, with the two hases in juxtaposition. The hody of this middle chamher is 

 rather stunted, its strength having heen apparently expended in the formation of a very 

 disproportionately long neck, which again widens out into a symmetrical flask-shaped 

 body, more ovate in form and somewhat wider in diameter than the preceding chamher, 

 the anterior part being also produced into a short straight neck. The shell is unique in 

 my collection, although I have met with a few forms which might possibly be fragments 

 of similar organisms, and would seem to connect Lagena with Nodosarina. 



Lagena VULGARIS,- Williamson, var. distoma-patera, Nov. (Eig. 58.) 



Shell somewhat goblet-shaped, with very bulging walls, slightly contracted round tli 

 top, where it terminates suddenly. Posteriorly the walls are well rounded ; and from tii 

 middle of the base projects an external tube of variable lenj^th and diameter. This tul) 



IS formed by the inflection of the shell-walls, and terminates very abruptly. The shell 

 is of a dirty white hue and very coarsely foraminated, the external walls also some- 

 times becoming irregular with exogenous shell-deposit. The basal tube has evidently bcvn 

 slightly broken ; whether this is the case with both ends I do not know ; but I have 

 met with many forms of this shell, and, though varying slightly in contour, they all 

 present very little difference from the example here delineated. 



In general outline this somewhat resembles the smooth form shown in fig. 54, the 

 neck being deficient and the basal tube more perfect. 



Lagena vulgaris, Williamson, var. Janeta, Nov. (Pigs. 59, 59«.) 



This shell is perhaps the most remarkable and interesting of all the distomatous 

 forms, having a peculiarity of structure which is unexampled in any other of these 

 microzoic forms. The shell-walls throughout are smooth and glassy, being also apparently 

 imperforate. The anterior portion of the structure has the form of a very elegantly 

 shaped flask, the base of which is rounded, and provided at its centre with a very small 

 circular orifice. This flask rests in, and opens into, a small " cup," which has a slight 

 constriction round its walls, and is perforated at its posterior extremity. From the base 

 of this cup the shell-walls form a long tube, which commences by turning suddenly to 

 one side, out of the axial line, and, envelopiug part of the side wall of the cup, makes the 

 channel of communication only half the width it would otherwise have been. It then 

 takes a downward course, though still at a considerable angle, and, widening gradually as 

 it mcreases in length, terminates very abruptly, after ha^-ing attained more than half the 

 length of the entire structure. 



"V^'iiether this is an adventitious or a normal groAvth, I leave for future investigations 

 to solve. Por the present, at any rate, it must be enrolled as a distinct variety. 



I'ig. 69 a represents a sectional outline, showing more clearly the details of the 

 structure. 



I^GENA VULGARIS, Williamson, var. hicamerata, Nov. (Pigs. 60-62.) 

 Shell consisting of two chambers, the primordial one being more or less globular, and 



^OL. XXX. K 



