Macalister — Muscular Ano?naltes in Human Anatomy. 127 
milating the carbonate of lime or tlie silica from its solution, and the 
organized form thus given to these substances is purely accidental. It 
is characteristic of our authors, that, rather than admit the limestone 
beds of the Eozoon rocks to have been formed like beds of coralline 
limestone, or deposited as chemical precipitates like travertine, they 
prefer, as they assure us, to regard them as the results of that 
hitherto unheard-of process, the pseudomorphism of serpentine ; as 
if the deposition of the carbonate of lime in the place of dissolved 
serpentine were a simpler process than its direct deposition in one or 
the other of the ways which all the world understands ! 
MoNTBEAL, January 16, 1871. 
XXI. — On Mtjsculae Anomalies est Huivian Anatomy. Ey Alexander 
Macalistee,, Professor of Zoology, T. C. D. [Abstract]. 
[Eead January 23, 1871.] 
In this Paper I have recorded all the muscular anomalies which 
have been seen by me during the past twelve years in the dissecting- 
room of the Eoyal College of Surgeons, together with notes of many 
others which have been communicated to me by several friends and 
former pupils. These I have tabulated in anatomical order, and I 
have, as far as I could, given a complete bibliographic record of the 
subject of abnormal myology ; there are thus in the list about two 
thousand forms of deviation from the average structure in man, over 
fifteen hundred of which have been noticed by myself. Of these, about 
a hundred and fifty are novelties, not hitherto described, as far as I am 
aware. I have not appended to this Paper any generalities, as I have 
seen no cause to alter any of the opinions which I have before expressed 
C^Proc." E. I. A., 1867, Dec. 9). JN'or have I added any remarks on 
muscular homologies ; for though I have seen reason to depart in 
some respects from the theory laid down in the paper just quoted, 
yet I desire that this paper — long enough in itself — should not be 
encumbered with any theory; and I have therefore carefully con- 
fined myself as much as possible to matters of fact. The most in- 
teresting question regarding muscular anomalies is that which concerns 
the relations existing between the departures from average structure 
in man, and the average or normal arrangements in lower animals ; but 
I have not, except in a few instances, touched upon this, as it would 
have swelled the paper to inordinate size. Muscles do not seem to 
vary in lower animals to the extent they do in man, though of course 
we cannot absolutely know the frequency of such anomalies unless we 
obtain a record of a much larger number of dissections as data than 
we have at present. In such animals, however, as I have several 
