200 General Notes. [February, 
maining three fingers. This anomaly was found by M. Testut 
on both arms of one subject. In the orang, not only are the two 
deep flexors united, but there is no tendon for the thumb, and 
this abnormality has been observed in man by Gruber, Wagstaffe, 
Gegenbaur, and Chudzinski. M.Testut believes that he can trace 
the presternal muscle, which in three or four per cent of the 
human subjects that have been dissected is present, and is con- 
nected above with the sterno-mastoid tendon and below to the 
great oblique, to the condition of things which obtains in ser- 
pents (or rather in vertebrates deprived of a sternum) in which 
the great oblique is attached to the mastoid apophysis. The 
sterno-mastoid and great oblique muscles are identical in their 
position with regard to the tegument, their direction, and their in- 
sertion on the haemal axial line, but where a sternum is present, 
the muscular fibers which descend from the mastoid apophysis 
find insertions upon it and upon the clavicle, and the part inter- 
vening between these insertions and what is now the great 
oblique becomes atrophied. Muscular anomalies are frequent 
in man, but M. Testut, in an important work upon this subject, 
shows that the muscles subject to these anomalies, which dis- 
appear entirely in some, while in others they are abnormally 
developed, are muscles which play an unimportant part in the 
human economy, and are links which unite man to the lower 
animals. 
EMBRYOLOGY.' 
THE DEVELOPMENT OF THE Rays OF osseous FisHes.2—Since 
the time when Vogt published his work on the development of 
the salmonoids, in 1842, it has been known that the earliest traces 
of rays to be noticed in the fin-folds of young fishes were fine, 
very numerous filaments, lying parallel to each other. Th. Lotz, 
in 1864, carried Vogt’s observations farther, and thought he 
showed that by the coalescence of these filaments the rudiments 
of the permanent rays were laid down. Both A. Agassiz and 
myself have found these filaments in the embryo of numerous 
widely separated genera of teleosts; the former having also 
pointed out their existence in Lepidosteus. They also exist per- 
manently in an almost unmodified form in the Dipnoans, as 
shown by the researches of Giinther and others, Balfour and 
myself have found these filaments in all of the fin-folds of Elas- 
mobranchs, though they seem to be wanting in the more fleshy 
pectoral of some of the Rays, They are present in the fin-folds of 
embryo sturgeons, and there probably give rise to the permanent 
1 Edited by JoHN A. Ryper, Smithsonion Institution, Washington, D. C. 
bstract of portion of a paper on the theory of the fins, to be published, with 
plates, in the Proc. U. S. Nat. Museum ” ee F 
“, seva die Schwanzwirbelsãule der Salmoniden, etc. Zeitsch. f. wiss. Zool., XIV, 
2 
+ 
DRE EI ESIE ee oy ST Rr es EERO OG ENE ee 
