ON THE GENERAL MORPHOLOGY OF THE MYXINOID FISHES. 709 
lies near the ventral surface of the now much folded velum, and which has a very 
ragged or “mossy” posterior border. Behind this border there may be several detached 
nodules of cartilage. The posterior portions of the external bars are placed asymmetrically 
somewhat near the middle line, under the dorsal surface of the velum, and continue 
so for the remainder of their course. The internal bars are prolonged beyond the 
posterior transverse bar, and curve first outwards and then upwards and inwards 
under the surface of the velum, until they reach the dorsal surface, where they 
terminate over the extremity of the external bars. 
The skeleton of the velum is subject to some variation, especially as regards the 
suprapharyngeal skeleton and the irregular processes from the posterior border of the 
posterior transverse bar. In one specimen there were three distinct rods arising from 
the latter bar—a median shorter one and two longer symmetrical ones. In this connec- 
tion, compare figs. 2 and 16. In Bdellostoma, according to J. MULuER, Parker, and 
AvERS and Jackson, there is only one process from this bar—a median one bifid behind. 
Myxme agrees with Ayrrs’ and Jacxson’s account of Bdellostoma except in one 
striking respect. The suprapharyngeal plate or cartilage of these authors is clearly the 
expanded posterior plate of the rod sp. sk.”, but the anterior rods sp. sk.’ do not end 
blindly but are fused to the antero-external angles of the above plate. Without 
wishing to cast doubt on this description, which may be based on a variation or on a 
different species, it must be mentioned that the descriptions of the suprapharyngeal 
skeleton of Bdellostoma given by J. MiLumr and W. K. ParKer agree essentially with 
mine of Myxine—except that Parxer missed the plate sp. sk.” in Myaine, and describes 
it in Bdellostoma as a thin rod bifid behind. 
K. SKELETON OF THE CLUB-SHAPED MUSCLE. 
This consists of two bars, placed one above the other, at the posterior extremity of 
the muscular complex known as the club-shaped muscle. I describe them now as found 
in a 35 cm. Hag. 
Inferior Chondroidal Bar.—This is composed of perfectly typical hard cartilage 
throughout, with the matrix very strong superficially in older specimens. The posterior 
portion of its length (8 mm.) comes to the surface of the M. perpendicularis (P. 
FURBRINGER) at the mid-ventral line. This portion lies behind the posterior extremity of 
the M. copulo-copularis (P. F.; M. constrictor musculi mandibuli, AvYERs and Jackson), 
and gives origin to the fibres of the perpendicularis. In front of this region the bar 
disappears into the copulo-copularis for about 3 mm., the posterior fibres of the latter 
muscle being inserted into it. It was a slightly asymmetrical laterally compressed rod 
pointed behind and blunt in front, 11 mm. long and 1 mm. deep. It has no connection 
with the fibres of the M. longitudinalis lineuz (P. F.; M. retractor mandibuli, A. and J.). 
Superior Chondroidal Bar.—Consists of hard pseudo-cartilage exactly as in the 
posterior segment of the basal plate, but may contain here and there small nodules of 
