566 BULLETIN 82, UNITED STATES NATIONAL MUSEUM VOLUME l 



Characters. — This species may i)c distinguished from L. phalarujium by an examina- 

 tion of the cirri. These are proportionately shorter than those of L. phalangium and 

 do not taper distally, so that their outer portion appears considerably stouter. While 

 in the proximal third of the cirri the segments are of the same proportions as those in 

 the comparable part of the cirri of L. phalangium, in the distal half they become shorter 

 so that in the distal third they are usually only one-third again as long as broad, and 

 nuiy be shorter, nearly or quite as broad as long, or even broader than long. As the 

 segments become shorter, the distal dorsal edge often becomes somewhat swollen so 

 that the dorsal profde of the cirri is slightly scalloped and not smooth as in the cirri 

 of L. phalangium. 



In a series of 45 specimens from the Minch, off Ross-shire, which I examined at the 

 British Museum, the cirri are XIV-XXIV, 4.3-50 (usually 43-47), from 30 to 40 mm. 

 (usually between 35 and 40 mm.) in length. In 4 from oflf Cape Mondego, Portugal, 

 the cirri are from 40 to 45 mm. long with 42 to 48 (usually 43 or 44) segments. Car- 

 penter mentions a cirrus from a specimen from the Minch 47 mm. long with 51 seg- 

 ments, and another 35 mm. long with 48 segments. He records a cirrus from an 

 example taken by the Dacia on the Seine bank with 57 segments; but this is very 

 possibl}' a misprint for 51. 



Carpenter noted that the figures which he gave of the articidar faces of the radials 

 of the Scottish celtica would serve equally well as illustrations of the same parts in 

 phalangium, though in some Scottish individuals the oblique ridges separating the 

 muscular fossae from the intcrarticular ligament fossae are less oblique than in those 

 he figured, and he did not find this to be the case in any examples of phalangium which 

 he examined. 



In all the Scottish specimens studied by Carpenter the IBri were oblong in their 

 general outline and but little incised, while the axillaries were subtriangular, sub- 

 quadrate, or more usually pentagonal with their bases curving slightly outwards. 

 The deep incision of the IBri by the axillaries sometimes seen in phalangium does not 

 occur. 



According to Carpenter the triangular brachials beyond the second syzygy are 

 distinctly shorter in the specimens from the Seine Bank and from the Minch than in 

 the Mediterranean phalangium, and this difference is still more marked in the outer 

 part of the arm where the brachials become wedge-shaped. 



The distal intersyzygial interval was determined in specimens from the Minch in 

 27 cases, and found to be: 2 muscular articulations, once; 3, 10 times; 4, 10 times; 

 5, 5 times; and 6, once. 



Carpenter wrote that the length of the oral pinnules is usually somewhat less in 

 the Scottish celtica than in the Mediterranean phalangium. Marion gave an average 

 length of from 12 to 17 mm. for the 4 lowest pinnules. These reach 15 mm. in the 

 largest example from the Seine bank, but Carpenter never saw any Scottish specimens 

 in which any of the 4 lowest pinnules were more than 13 mm. long. The discrepancy 

 between the first 2 pairs of pinnules and those succeeding is somewhat greater in celtica 

 than in phalangium. 



Carpenter noticed that the broadening of the first 2 segments of the distal pinnules 

 is more marked in the Scottish celtica than in phalangium. The shape of the first 

 segment is the same in both forms; but as a rule the second is relatively narrower in 

 phalangium so that the distinction between it and its successors is less nuxrked than 



