338 RAYMOND PEARL. 



cover no record of such a condition has been made in teratologi- 

 cal literature, nor is such a condition found normally in any 

 form. In most mammals 1 the latissimus inserts by one tendon ; 

 in some forms (e. g., the cat) usually by two; and finally as a 

 variation, which apparently occurs with some frequency, it inserts 

 by two tendons in forms where it normally has only one. This 

 last is the condition in man. 2 



The condition found in this abnormality to a certain degree 

 resembles morphologically what is normally found in many 

 mammals in the M. epitrochlearis. This muscle, in the majority 

 of cases, takes origin from the surface of the latissimus dorsi 

 near its insertion, and is inserted into the superficial fascia of the 

 forearm and the olecranon. This muscle is usually regarded as 

 a differentiation product of the latissimus dorsi. It is possible 

 that the present abnormality may indicate that originally the M. 

 epitrochlearis had in the carnivora a greater extent at its inser- 

 tion, extending on to the superficial fascia of the upper as well 

 as the forearm. Further than this I am not able to make any 

 suggestion regarding the significance of this abnormality. On 

 account of the fact that apparently such a case had not been de- 

 scribed, it seemed desirable to make a record of it. 



II. A CASE OF CONNECTION BETWEEN THE M. CLEIDOMASTOI- 



DEUS AND THE M. LEVATOR SCAPULAE VENTRALIS. 



The M. cleidomastoideus normally forms a distinct muscle in 

 the cat, taking its origin from the apex and caudal margin of the 

 mastoid process of the temporal bone. It passes caudad, flatten- 

 ing during its course, and is inserted on the lateral four fifths of 

 the clavicle and laterad of the clavicle on the clavicular raphe. 

 This clavicular raphe is formed between the Mm. cleidomastoideus 

 and clavotrapezius (= M. cleido-occipitalis + cleido-cervicalis 

 Streissler) 3 craniad, and the M. clavobrachialis (= Pars claviculi 



J Cf. Leche, W. , Mammalia, in Bronn's " Klassen u. Ordnungen des Thier- 

 Reichs," Bd. 6, V. Abth., 1874-1900, pp. 722-725. 



2 Cf. Le Double, A. F., " Traite des Variations du Systeme Musculaire de 

 1'Homme," Paris, 1897, T. I., pp. 194-202. 



Testut, L.,"Les Anomalies Musculaireschezl'Homme," Paris, 1884, pp. 106-118. 



3 Streissler, E., " Zur vergleichenden Anatomic des M. cucullaris und M. sterno- 

 cleidomastoideus," Arch. f. Anat. (u. Physio/.) Jahrg., 1900, pp. 335-365, Taf. 

 XXI. u. XXII. 



