ON THE GENERAL MORPHOLOGY OF THE MYXINOID FISHES. 769 
trabeculare anterius”). With special reference to these unexpected results I worked 
over very carefully Dr Brarp’s sections of a 6°5 Hag—a younger form than any at 
NeuMAYER’S disposal. I must point out that this specimen had been somewhat 
damaged before coming into Dr Brarp’s hands, that it was not, in fact, properly 
preserved, and that the sections are very irregular. Nevertheless I think I can 
positively state that, excepting to a certain extent the nasal tube, NeumMayer’s results 
are either hopelessly inaccurate or that there must be some explanation of them that 
does not occur to me. It is difficult to believe that a careful and laborious worker as 
Dr NEuUMAYER is well known to be could be so far in error, and we must therefore await 
a re-investigation of the embryonic skeleton of Myxine. As we should expect, and as 
pointed out by BEarp* and Neumayer, the nasal skeleton is relatively very large in the 
young forms. The reconstruction of the nasal skeleton given by Pottarpt is in exact 
acreement with my fig. 1, based on dissections. 
G. THe TenracuLar Apparatus. (Figs. 1 and 2.) 
Omitting the problematical tentacles mentioned in connection with the nasal 
skeleton, there are four tentacles on each side both in Myzine and Bdellostoma. These 
are the nasal and oral barbels of W. K. Parker. Of them only one, the fourth, has an 
independent skeleton, that of the other three being fused with portions of the internal 
framework. I therefore describe under the above head the subnasal cartilage or bar 
and the lateral labial cartilage, but this is done simply as a matter of convenience. The 
whole of the apparatus consists of soft cartilage, except the central portion of the 
subnasal bar and the free internal extremity of the cartilage of the fourth tentacle. 
All the cartilages extend to the tips of the tentacles. 
The cartilage of the first tentacle (1), morphologically the second, passes downwards 
and backwards at the side of the nasal opening, crosses externally the base of the second 
tentacle, and terminates blindly on the surface of the muscles at about the level of the 
subnasal bar. A short distance before it terminates, it fuses by its posterior surface 
with the lateral “labial” cartilage (l. 1. ¢.). The latter passes at first upwards and 
backwards to give off a projection, the wternal process, into which the M. nasalis is 
partly inserted. Ayers and Jackson state that this process in Bdellostoma is attached 
to the nasal tube by a membranous ligament, but in Myxine it is only imdvrrectly con- 
nected with the nasal tube and skeleton by means of the insertion of the M. nasalis. 
Also in Bdellostoma, according to J. MOLLER and Ayers and Jaoxson, the anterior 
extremity of the lateral labial is connected by ligament with the tip of the cornual 
eartilage.{ Behind the internal process, the lateral labial bends downwards and back- 
wards in a slight curve, and receives ventrally the cartilage of the third tentacle (38), 
which fuses with it. The latter cartilage is a stout rod, thicker at its base than the 
* Anat. Anz., vili., 1893, p. 59. 
+ Zool. Jahrb., Abt. Morph., viii. ; Taf. xxv., fig. 11, 1895. 
{ Cp. the description of the latter cartilage. 
