CHAETOGNATHA COLLECTED BY STEAMER ALBATROSS. 241 



Vestibular ridge (pi. 34, fig. 3) well developed with large papillae. 

 Wing of ridge covers all but the first two or three teeth, the notch 

 extending to the fourth or fifth. External process long and blunt. 



Anterior teeth (pi. 34, fig. 2), nine in number. They are short, 

 broad, closely set, and diverge but little distally. 



Posterior teetli (pi. 34, fig. 3), 20 in number. They are long, 

 narrow, closely set, and diverge even less than do the anterior teeth. 



Seizing jaws (pi. 34, fig. 4), six in number. Point with an oval 

 base imbedded between 20 and 25 per cent of its height into shaft. 

 Top of shaft and base of point converge toward edge of jaw. Edge 

 of shaft provided with narrow crest. Pulp canal central and slightly 

 swollen at base of point. Pulp evenly distributed. 



Only a single specimen was obtained. Its measurements follow: 



Length 13 mm. 



Width 5. 5 per cent of length. 



Length of tail 23 per cent of length. 



Tip of tail to posterior end of ventral ganglion 70. 5 per cent of length. 



Length of ventral ganglion 6. 5 per cent of length. 



Length of posterior fin 22 per cent of length. 



Width of posterior fin 4. 5 per cent of length. 



Interval from anterior to posterior fins 6 per cent of length. 



Per cent of posterior fin in front of tail-septum 60 per cent. 



Length of anterior fin 30 per cent of length. 



Width of anterior fin 2. 5 per cent of length. 



Anterior fin extends beyond posterior end of ventral ganglion 



by 2 per cent of length. 



Ovary extends beyond posterior end of posterior fin by 14 per cent of length. 



Anterior teeth 9-9 



Posterior teeth 20-(?) 



Seizing jaws 6-6 



The single specimen (Cat. No. 17801, U.S.N.M.) was taken from 

 the surface May 14, 1908, off Uanivan Island, at station D 5240, 

 latitude 6° 49.5' north and longitude 126° 15' east. The same haul 

 also yielded 130 S. enfiata, 10 S. ferox, 6 S. hexaptera, 1 P. draco, and 

 75 S. decipiens. 



S. pliilippini bears a strong resemblance to the latter species, but 

 differs from it in several important details: In the first place, it has 

 no trace of a collarette, although this structure, while not pronounced 

 in S. decipiens, is conspicuous. Again, the ovaries of S. pTiilippini, 

 though not fully mature, extend nearly to the middle of the anterior 

 fin, while in S. decipiens they do not, when mature, extend beyond 

 the anterior limit of the posterior fin. Further, the posterior fin of 

 S. pliilippini is rayed throughout, while in S. decipiens (pi. 35, fig. 8) 

 the anterior fourth or fifth of the fin is rayless. Lastly, the seizing 

 jaws of the two species are quite different (pi. 34, fig. 4, and pi. 37, 

 fig. 22), the jaw in S. philippini being provided with a narrow but 

 conspicuous crest, which is missing in S. decipiens. 



