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



PI. 15, fig. 15 shows the lines assuming an S-shaped condition. 

 Locality : Occurs rarely at two or three stations. 



It is impossible in certain cases to separate the striate from 

 the very finely costate forms, but many are undoubtedly costate. 

 They are rarely in the apiculate condition. 



Lagena costata Williamson sp. (PL 15, figs. 16-20, 21). 

 Entosolenia costata Williamson, 1858, p. 9, pi. 1, fig. 18. 



The specimens are numerous. Both the strength of the costae 

 and their number vary greatly. Type specimens are present. 

 Locality : Various stations. 



The following are interesting examples : 



PI. 15, fig. 16. This has a slightly projecting ring at the 

 base. Locality : About a dozen from various stations. 



PI. 15, fig. 17. An odd specimen. Locality : No. 29. 



PI. 15, fig. 18. In this the costae are only six in number. 

 Only one occurs. Locality : Uncertain. 



PI. 15, fig. 19. In this the costae are curved and well developed. 

 Only one found. Orifice circular. Jjocality : The exact locality 

 is uncertain. 



PI. 15, fig. 20. In this some of the costae only reach jjart way 

 down the test. The mouth is circular. There are two or three 

 specimens on the slide. Locality : Exact locality uncertain. 



PI. 15, fig. 21. As there is only a single specimen to judge 

 by, and that one somewhat asymmetrical, it is placed here with a 

 query against it. It is quite opaque. The orifi.ce is a simple 

 opening, with three radiating fissures. I thought it might 

 possibly be a seed case, but on touching it with hydrochloric 

 acid I found that it at once effervesced. It seems to be allied to 

 Trigonuli7ia glohosa Seguenza, 1862, pi. 2, figs. 60-62. Ljocality : 

 No. 3. 



Lagena acuticosta Reuss (PI. 15, figs. 22, 23). 

 Lageiia acuticosta Peuss, 1861, p. 305, pi. 1, fig. 4. 



This is an unsatisfactory species, for it is simply a form of 

 L. costata. The few specimens that occur are similar to the 

 Challenger figure, pi. 58, fig. 21. 



PI. 15, fig. 22 is practically the same as the Challenger figure, 

 pi. 57, fig. 32. Locality : No. 3. 



