THE MARSIPOBRANCHII. 148 
organization is not so much the sucking lip, as is most 
frequently supposed, but the rasping tongue?* ‘The more 
salient structural pecularities of the heads of these animals 
may be read off in relation to this, as may be those of the 
Lamellibranchiate mollusca, for example, in relation to 
the absence of the head itself. And, moreover, the fact 
that the common lampern ‘“‘ consumes water insects and 
the flesh of dead fish’’+ and that of the regular capture of 
Hags on the long-line hooks, go far towards suggesting 
that the extent to which a parasitic habit may have induced 
these peculiarities has been grossly over-estimated. 
IX. The paleontological history of the Marsipobranchii, 
until lately estimated upon the supposition that the 
Conodonts, some of which have been claimed as annelid 
jaws,{ are Marsipobranch teeth, has recently undergone a 
revolution, in Traquair’s description§ of a very remarkable 
fossil from the Old Red Sandstone at Caithness, which he 
has named Paleospondylus gunn, after its discoverer. 
In his preliminary paper he remarks (p. 485) on the 
presence of ‘‘ vertebral centra’’ which are ‘hollow or 
ring-like” and states (p. 486) that ‘‘a Myxinoid with 
ossified skeleton . . . is a rather startling idea.” 
From careful examination of a duplicate specimen which 
Dr. ‘Traquair has very generously given me, I fully ac- 
quiesce in his having provisionally referred the creature 
to a Marsipobranch affinity, and look upon the noto- 
* Parker has already proclaimed this for the Myxinide (Phil. Trans., 
1883, pp. 381 and 382). . 
+ Francis Day, in Fish. Exhib. literature. London, 1884. Vol. VIII, 
p. 326. 
+ Rohon and Zittel, Sitzungsb. d. k. bayerisch, Akad, 1886, p. 108. Dr. 
G. J. Hinde, who has paid considerable attention to these structures (cf. Qu. 
Jour, Geol. Soc., vol. 35, p. 370) informs me by letter that he has ‘‘ no doubt 
of the complete distincness ” of the two. 
Ann. and Mag. Nat, Hist., Ser. 6. Vol vi., 1890, p. 485. 
