078 MESSES. B. C. A, AVINJJLE AiSJJ F. G. PAKSOSS ON [DeC. 17, 



ments of the scalenus longiis aud brevis are more or less confused, 

 and that the attachment of the longus to the first rib might, in 

 many cases, be more fitly described as brevis ; but the difficulty of 

 satisfactorily separating the two muscles is such, that those who 

 ha^e dissected most will be least inchned to criticize our inability 

 to be definite. One way out of the difficulty would be to only 

 call those fibres \^hich pass to ribs behind the first as scalenus 

 longus ; but this would only be meeting one difficulty with another, 

 since, in some cases, there are distinctly two insertions into the 

 iirst rib dorsal to the brachial plexus. 



Summing up, we may say that the Oanielidae (we have no 

 records of the Llama), the Cervidse, the Sheep, and the Equidae 

 have no prolongation of the scalenes beyond the first rib ; while in 

 the other families (? Ehinocerotidse) the scalenus longus usually 

 reaches the third rib, and in the Procaviidso may be prolonged 

 back as far as the sixth. The arrangement in the Sheep, of which 

 we have many records, is especially interesting, since it forms 

 another sharp myological contrast with the Goat. Steel's observa- 

 tion (XIX.) that the Ass has occasionally a prolongation of the 

 scalenus longus to the third rib, points to the fact that that 

 animal is less highly specialized than the Horse. We are more 

 than ever convinced of the futility of attempting to homologize 

 the scalenus longus and brevis individually with the scalenus 

 medius and posticus of Man, since the brevis in its dorsal position 

 corresponds to the Man's posticus, but the longus is the muscle 

 which goes beyond the first rib, as does the scalenus posticus of 

 Man. The nerve-su.pply of the scalenes is from the upper trunks 

 of the brachial plexus. 



Eeotus capitis ventralis (anticus) major rises from the trans^'erse 

 processes of the third and two or three succeeding cervical vertebrae 

 and is inserted into the basioccipital. There is nothing special to 

 remark about it. 



Hectvs capitis ventralis (anticus) minor. — Chauveau (II.) in the 

 Horse and Kinberg (X.) in the Chevrotain point out that this 

 muscle lies external to the last, and we found the same muscle 

 rising from the atlas and axis in the Pig (11) and the Brocket 

 Deer (27). Unfortunately we failed to look carefully for this 

 in the other animals we dissected, but the records we have 

 show that it is at least of frequent occurrence in the Ungulates. 

 We have some little doubt as to whether this muscle can be 

 liomologized with the r. c. v. minor of other mammals, or whether 

 it would uot be advisable to speak of it as r. c. v. externus. 



In Hyrax (67), Mivart and Murie failed to find the minor in its 

 usual place, but we found a few fibres running from the ventral 

 arch of the atlas to the basioccipital (68). 



Longus colli. — Lesbres (V,) and Kinberg (X.) point out that the 

 vertical fibres of this muscle are absent and only the two oblique 

 parts present. The lower oblique portion usually comes from the 

 anterior six thoracic vertebrae, though in the Camel (18) and 

 Mouflon (45) it only reached the fourth. Steel (XIX.) points 



