114 



from the more thinly muscular ptera in Ptcrophysa grandis. An enlarged sketch of the second 

 siphon is given on PI. XXII, fig. 154. It is situated at a distance of 24 cm. behind the first 

 one and does not show any important difference. The pedicle is as clearly developed as in 

 Bathyphysa. There is no sign of any tentacle or indication of a j-oung one. The stem between 

 the first and second siphon attains its greatest breadth. (8 mm.). It shows manv turns and at 

 irregular intervals small protuberances also of the same muscular structure (PI. XXIV, fig. 171). 

 We suppose these to be the imj^lantation of detached siphons, and as we counted 72 of these 

 small swellings, 75 siphons were probably situated on the stem before the specimen was ca])tured. 

 Of these 72, three were present in the same bottle: together with a vast amount of tentacles, 

 and stems and other appendages, impossible to determine, but which to judge by their muscular 

 structure may perhaps belong to Bathyphysidae. 



The third siphon (distance 1 2 mm. distally from the second) is mature, as the bristle 

 could be introduced quite easily. Its ptera are the same as in the two others, the entoderm ot 

 the central cavity shows peculiar notches which are also .slightly visible in the second. Its length 

 is 35 mm., its breadth 9 mm. with the ptera. The stem behind this third siphon shows many 

 alterations in breadth, but no appendages are more "string"-like than the proximal part. 



Bathyphysa Studer 78. 



59. Bathyphysa Sibogae nov. spec. PI. XX, fig. 148; PI. XXIII, figg. 160 — 1O4; PI. 



XXIV, fig. 173. 



Stat. 38. Lat. 7°35'.4S., Long. ii7°28'.6E. Depth 521 M. Trawl. Fi.xation in Cu SD^ 10°/^, 

 formald. 4°/^. Cat. 27 A. One specimen and Cat. 27 R. (detached appendages 

 of 27 A.). 



Stat. 227. Lat. 4°5o'.5S., Long. I27°59'E. Depth 2081 W. Deep-sea trawl. Cat. 5 A., 5 B. 

 (detached appendages of 5 A.), formald. 4°/o. One specimen. 



Cat. 5 A. is one of the most remarkable Bathyphysidae found in the Siboga material. 

 It is called Bathyphysa as it possesses clearly-marked pedicles at the base of the siphon. Of 

 course the specimen as it is drawn on PI. XXIII, fig. 160 is not complete and a living Bathy- 

 physa Sibogae has, no doubt, a totally different aspect. There are, however, many characteristics 

 which will make it quite easy for later investigators to make the comparison of their material 

 with ours. Cat. 5 A. is the longer specimen of the two, it has a length of about 72 cm. Its 

 pncumatophore (PI. XXIII, figg. 160, 161) has a length of 9 mm. (measured externally up to the 

 first bud of the siphon) and a breadth of 4 mm. The silvery wall of the pneumatocyst shines 

 through distinctly; we cut away a small part distally and found that behind the h\pocystic 

 funnel there are clearly-developed though very small hypocystic villi. This may be a difference 

 from Bathyphysa abyssorum Studer but as in the latter the pncumatophore had burst (PI. XXIV, 

 fig. 166) the villi may have become detached. Pigmentation near the porus is not to be found, 

 it has gone probably through preservation; the porus itself is visible as a clearly-marked 

 aperture (PI. XXIII, fig. 161). The first buds of young siphons appear even immediately above 

 the place where the hypocystic villi are found interiorly. They very soon become developed, 

 and attain a length of 3 — 5 mm.; the stem at this point has a breadth of 4 mm. and shows 



