THE ANNALS 
AND 
MAGAZINE OF NATURAL HISTORY. 
[FOURTH SERIES. ] 
No. 5. MAY 1868. 
—_—— 
XXXIX.— Contributions toward the formation of a correct Sys- 
tem of Muscular Homologies. By ALEXANDER MACALISTER, 
M.D., L.R.C.8., L.K.Q.C.P., Demonstrator of Anatomy, 
Royal College of Surgeons, Ireland, one of the Honorary 
Secretaries of the Royal Geological Society of Ireland *. 
THE literature of comparative anatomy is teeming with me- 
moirs and essays on that department of homology which treats 
of the serial comparison of the muscles of the fore and hind 
extremities in vertebrate animals. 
Almost every writer has originated an hypothesis of his own 
(some of these being plausible and some fanciful), starting from 
which he proceeds to work out details, some of which in all 
theories are undoubtedly true; but every author has differed 
from his predecessors and successors in his reading of these 
serial homologies. In the majority of these theories muscular 
peculiarities have been regarded as subsidiary to osseous ar- 
rangements, and many authors have deduced their ideas of 
homotypical myology from the study of bones rather than 
from the direct con cderatiosk of the muscles themselves and of 
their relative positions, courses, and attachments. Such being 
the present position of this branch of comparative anatomy, no 
apology is needed for bringing forward any observations which 
may ete a have the advantage of novelty, and which may 
elucidate in some degree the vexed question of serial homo- 
logies. A great number of the misapprehensions into which 
anatomists have fallen with respect to these homologies are due 
to the fact that the individual components of the fore limb of 
a limited number of animals have been compared directly with 
those of the hind extremity, irrespective of the differences of 
the work to which they may be devoted; but this is a mistake 
in principle, and one from which we may free ourselves by 
* Communicated by A. Carte, M.D., Dublin. 
Ann. & Mag. N. Hist. Ser. 4. Vol. i. 23 
