182 William Sörensen 
and 4), and other Siluroide is precisely the »Basale« encased in the 
ray — and fused in Salmo with the upper half of it, in the Silu- 
roid with both halves. But what in his Fig. 43 is marked with 
» H« (»Kegel«) in Salmo, is the upper end of the articular part, i. e. 
of the »Basale«; the limit between this bone and the upper half of 
the ray being tolerably distinct in the specimen examined by me. 
And even a hasty look at Figg. 3 and 4 in the present paper, will, I 
am sure, show the reader that the process 0 has nothing to do with 
the articular face, with the »Basale«. In fact it is a process of the 
upper half of the ray. — In Triacanthus Dr. TmıLo appears to me 
to have seen that the »Hemmfortsatz« (in the ventral fins) is a pro- 
cess of the ray!; in this genus too I suppose the said process to 
be a process of the upper half of the ray. 
4. That, as to the function, the process 0 is no part of the 
diarthrosis, is clear beyond question, I suppose, from the reasons stated 
under the heads 1 and 2. That it is not so either, morphologically, 
appears to me evident partly from what I have stated just now, 
partly also from what follows: There does not exist one fish in 
which any of the pectoral rays articulates with the bone, called by 
CuviER »Humerus« but by GEOFFROY ST. HILAIRE and GEGENBAUR 
»Clavieula«. I have dissected the pectoral fins in a considerable 
number of fishes. But of course I have not by far dissected so many 
fishes as CuvieR et VALENCIENNES and partly from this reason, 
partly in order to show that this knowledge had been gained a 
good while ago, I quoted in my book a passage from these authors?: 
»De plus, il n'est pas vrai, comme le dit M. GEOFFROY, que ce rayon 
pectoral du silure s’articule 4 Vhuméral (quil nomme clavicule); 
mais il s’articule au radial [the »scapula« of GEGENBAUR], comme 
le fait toujours le premier rayon pectoral, et méme par une articu- 
lation toute semblable. Seulement cette articulation a une saillie 
courbe, qui pénétre dans une fossette de Vhuméral, ot elle peut 
prendre une situation fixe par un léger mouvement de torsion.« — 
! Pag. 328: »Der Hemmfortsatz ist somit nichts Anderes, als einer jener 
Knochenzapfen, die häufig in der Nähe von Gelenken beobachtet werden.« 
2 For when Dr. THuıLo expresses the opinion that the »Hemmfortsatz« in 
Triacanthus »aus zwei Knochenzapfen entstanden ist«, then I must consider 
this to be quite impossible, for it would involve the spine’s being a fusion of 
two rays; and there is not the slightest reason for such a supposition. 
3 QUVIER et VALENCIENNES, Histoire naturelle des Poissons. T, XIV, 
Paris 1839. pag. 318. 
