Thilo’s memoir on »Die Umbildungen an den Gliedmaßen der Fische«. 183 
That Dr. Tutto has seen this quotation in my book, appears from 
his paper. 
Now, as the »Humerus« never articulates with any ray of the pec- 
toral fin in other fishes, as the process 0 is not a process from the 
articular part (the »Basale« of GEGENBAUR) of the first ray, and as 
it does not serve to effect but, on the contrary, to stop, prevent or 
impede the movements of the ray, then neither from a morphological 
nor from a physiological point of view can this process be considered 
as part of the diarthrosis. 
That the scouring faces of the unpaired fins in all the fishes 
which I have examined, form no part of the diarthrosis, is in my 
opinion beyond question. Whether they may be considered, mor- 
phologically, as being parts of the diarthrosis, I must leave undecided. 
Monacanthus pardalis L. The dorsal fin. (My book, pag. 53—55.) 
»The anterior dorsal fin is well known to consist of two rays, 
of which the foremost is a long and strong spine, connected with 
(Copy of Fig. 8 in my book.) The first dorsal fin, part of the skull, and the common interspinous 
bone from the left side; natural size. The rays are erect, but not fixed. — Cr, the skull; no 
limits are shown between the skull and Sb, the first interspinous bone. — Or, Orbita. — J, the first 
ray (the upper part broken off), k, the hookformed process of the 1st ray (but partly visible). — 
IT, the second (rudimentary) ray. — 0, the scouring face on its foreside. — 0!, the scouring face on 
the middle crest of the interspinous bone (but hardly visible). — A, A, 2', ligaments. — a!, a2, M. 
anterior of the first and second ray. — p!, p2, M. posterior of the same rays. 
the interspinous bone by means of a diarthrosis of the same form 
as in Balistes', strengthened by a very strong ligament (A) which 
! The diarthrosis of the first ray of Balistes I left totally undescribed; 
I only referred to HoLLARD, adding that I had nothing new to say on this 
subject, 
