THE MARSIPOBRANCHII. lat 
meet in the middle line below, and their relationships to 
the ‘‘styliform processes’’ (st.) are so closely identical 
with those of the ‘‘cornual cartilages” in the Lamprey, 
(cn.) except for the confluence between the two, that the 
homology with them can hardly be doubted. Of the four 
anterior ones, the outer two (v.e. fig. 2) are, as Joh. 
Muller showed, intimately connected with the lip supports, 
through the mediation of the afore described T piece, 
while the inner pair (v.2.) he closely related to the anterior 
extremity of the great lingual (antero-ventral) cartilage 
(a.v.). Comparison with the Lamprey is here most sug- 
gestive, for the insignificant antero-ventral element of 
that animal (fig. 1, a@.v.) bears a couple of upstanding rods 
(v.i.) having very much the same relations as these; while, 
in their intimacy with the lip supports and their relation- 
ships to the descending branches of thé trigeminal nerve 
the outer pair resemble very closely the cornual appen- 
dages (v.e.) of that animal’s annulus. These three pairs 
of cartilages if homologous, as I herein attempt to show 
and fully believe, are to no slight degree inversely propor- 
tionate in size and functional importance in the Lamprey 
and Hag, and I am strongly disposed to seek the clue to 
this difference, in changes which have led up to that 
similar disproportion in the median lingual elements of 
the two types, already alluded to (ante. p. 134). 
In discussing the inter-relationships of the Lampreys 
and Hags, Huxley* and others have regarded the former 
as the more primitive, while Parker,+ Beard,t and others 
have reversed the order. That the Bdellostoma, with its 
independent gill openings in the condition of the Lam- 
prey’s, and its head skeleton and olfactory apparatus in 
* Jour. Anat. Phys. Vol. X, p. 428. 
+ Phil. Trans., 1883, p, 417. 
+ Zoolog. Jahrb., cit.. p. 742, cf., also Anat. Anz., 1885, pp. 15—24. 
