Gatty Marine Laboratory, St. Andrews. 113 



yet remains the closely allied and nearly as large Sigalion (?) 

 Buskii, McI.*, procured by Dr. Gwyn Jeffreys in Shetland, 

 with which to contrast the Italian author's species. Neither 

 the northern habitat (for only a single example has yet been 

 procured) nor the absence of eyes in this deep-water form is 

 of essential value. The head, however, differs in being pro- 

 portionally larger and more ovoid, and without the posterior 

 narrowing of S. squamatum. Instead of the two lateral 

 minute tentacles (like papillse) only a single small median one 

 occurs in this form, a remarkable condition in the genus. 

 The scales in S. Buskii, as a rule, have the transverse diameter 

 shorter than in S. squamatum, and the pinnate papillse along 

 the outer edge have no constriction at the base and taper more 

 distinctly towards the tip (PL II. fig. 15), being somewhat 

 lanceolate, to the number of ten or twelve on each side 

 in the largest. The simple papillae along the outer and poste- 

 rior edge of the scale at the bases of the foregoing are shorter 

 and more numerous. Moreover the central granular region 

 above the stem is more distinctly expanded than in the 

 Neapolitan form. Occasionally a pair of pinnae on opposite 

 sides of the stem branch into two or three points. The 

 pinnje of the papillae of S. squamatum are fewer in number and 

 have a slightly fusiform or lobate shape, that is with a tendency 

 to constriction at the base, and they are also, as a rule, fewer in 

 number than in S. Buskii, six being common. Very little dila- 

 tation of the axis occurs above the bare stem, which is generally 

 longer than in S. Buskii. The nerve-strand to the pinnate 

 papillae of the scales is somewhat more distinctly curved than 

 in S. squamatum, and the secondary twigs to the stems are 

 shorter. The foot in S. squamatum is slightly larger as a 

 whole than in S. Buskii and the ventral cirrus longer and 

 more tapered. The dorsal lobe has a much longer terminal 

 papilla (cestode), and the bristles are longer and apparently, 

 judging from the preparation, more delicate. The ventral 

 lobe of the foot is similar to that of S. Buskii, though in the 

 latter the stronger series at the upper edge of the lowest 

 group have a longer terminal process (bifid) than in S. squa- 

 matum. The Italian specimens, apparently from their mode 

 of preparation, had their bristles considerably injured, so that 

 an accurate comparison in every detail could not be carried 

 out. The two species S. squamatum and S. (?) Buskii 

 certainly approach each other much more than do the former 

 and S. Mathildce ; but there are sufficient reasons for sepa- 

 rating them, as the descriptions and figures show. 



• Trans. R. S. E. xxv. 3, p. 409, pi. xii. fig. 12, and Trans. Z. S. ix. 7, 

 p. 301, pi. Ixx. fig. 14. 



