750 MR FRANK J. COLE 
cluding section of a general character, in which the morphology of the Myxinoids will 
be treated in detail and the appropriate general literature discussed. ‘The present part, 
therefore, like its successors, is not morphological, but is concerned with descriptive 
anatomy only. A very full description of the muscles will constitute Part I., and will 
be ready by the end of the year. 
As regards the terminology of the skeleton, it is quite clear that the failure of Panes 
and Ayers and Jackson to correctly homologise the parts of the Myxinoid skeleton 
was due to insufficient data; and another attempt on my part, before the evidence of the 
muscles, blood-vessels, and nerves is available, and also the memoir on the development 
of the skeleton of Bdellostoma now being prepared by Neumayer, could only end in 
failure also. I have therefore adopted the terminology of Ayers and Jackson en bloc, 
not because I approve of it—in fact, some of their terms have already been successfully 
challenged by Attis—but simply to avoid coining a set of terms which could only last 
a few years.* In my concluding section I shall, of course, discuss the morphology of 
the skeleton, and revise the terminology, with, let us hope, a reasonable prospect of 
arriving at results of some lasting value. 
I have great pleasure in acknowledging the kindness of my friend Dr Bzarp in 
lending me his sections of Myxine, and especially the series of the 6°5 cm. Hag, which 
has been of great use to me. Also the collection of my own material was made 
possible by a grant of £50 from the Government Grant Committee, with which I visited 
the marine laboratory at Cullercoats, under the charge of Mr ALExanpER MeErx, and 
was entirely successful. Living Myaine may be collected at Cullercoats in great 
quantities, by methods which I shall describe in my Third Part. The laboratory at 
Cullercoats since my visit has unfortunately been entirely destroyed by fire, and it is to 
be hoped that the important work which Mr Menrx is doing there will not long be 
paralysed for the lack of a new well-equipped laboratory. Finally, I am greatly indebted 
to Professor W. F. R. WeEtpon, F.R.S., in whose laboratory at Oxford this work was 
done. 
B. Norocuorp. (Fig. 18.) 
The termination of the chorda at its cephalic and caudal extremities is described 
under the parachordal and caudal fin cartilages, and also below. As is well known, the 
notochord constitutes the only skeletal support of the back, and there is no appearance 
of cartilage, either in the chorda itself or in the neural tube, except in the region of the 
head and tail (q.v.). Still less are there any traces of bone or calcified tissue of any 
kind whatever, either here or in any other region of the body of Myxine. In this 
respect the Cyclostomes share with Amp/zoxus a unique position in the chordate series. 
* For example, the structures named ly Aymrs and Jackson “ branchial arches” are, according to BASHFORD DrEan, 
developed after the gill pouches have disappeared from this region, and may therefore represent neomorphs developed 
in connection with the muscles of the “tongue.” In fact, I am disposed to believe that much of the Myxinoid skeleton 
is recent and sesamoidal (as indicated by PonnaRrD), and therefore has no morphology at all! 
