HENRY SIDEBOTTOM ON LAGENAE OF THE SOUTH-WEST PACIFIC. 397 



test. The shaded portion represents the exogenous shell-growth. 

 Three tests are on the slide, but one of them does not belong to 

 this species. Locality : Nos. 20, 21. 



Note. It is impossible to deal satisfactorily with the different 

 forms of the compound-walled Lagenae unless good sections can 

 be obtained. I am at present unable to undertake the work,, 

 partly from not wishing to sacrifice specimens, especially when 

 very rare, and also from inability to use the very high-power 

 lenses which are necessary for the small specimens. It is not 

 difficult to grind down half the test, if you have specimens to- 

 spare for failures. Many of the tests, however, are exceedingly 

 friable, and once in the Canada balsam and heated, I doubt if 

 they would bear turning over, in order to procure thin sections. 

 It I will be understood that with, the test only partly ground down, 

 the illumination must be from above ; a difficulty which I cannot 

 overcome when using high-power lenses, no doubt owing to my 

 technical ignorance. The following descriptions are given to th& 

 best of my ability. 



Lagena hertwigiana Brady var. nov. undulata (PI. 16, 



figs. 26-28). 



There are about one hundred examples on the slide, and T 

 believe them to be a variety of L. hertvngiana. The test is round 

 in section, more or less ovate or pyriform in outline, with a long, 

 delicate neck which broadens out a little at the orifice. The body 

 of the test is covered with slight ridges, which give it a wavy 

 appearance. There is a single row of perforations between th& 

 ridges. The wall is compound and appears to be cellular. Brady, 

 in the Challenger Report, refers to a variety which has the per- 

 forations arranged in lines, as in Xodosaria inter celhdar is, but 

 does not mention the ridges. The long neck is rather mora 

 delicate than represented in my drawings. The tests are opaque 

 and of a light cream colour. Locality : Chiefly Nos. 1 3, 7, 13^ 

 17, 28. 



PI. 16, fig. 28. This varies from above in having the perfora- 

 tions much closer together and the ridges even less raised. It is- 

 semi-transparent and very rare. On breaking one of the specimens 

 a short, straight, entosolenian tube was revealed. The wall of 

 the test appeared to be cellular. 



