446 GENERAL ANATOMY. 



716. Certain muscles form one sole fleshy body between 

 the two attachments; others, on the contrary, are formed of 

 very distinct bundles, which might be taken for so many mus- 

 cles; such, in particular, are the masseter, the deltoid, the sub- 

 scapulary, the glutseus muximus, &c. 



717. There are muscles which in their whole extent re- 

 main simple and distinct, and others which are divided into 

 several parts, or confounded with others at one of their extre- 

 mities: thus, some mu'scles, simple at their insertion, are se- 

 parated, at their origin, into two or three parts: such are the 

 biceps and the triceps; such are also the sterno-mastoideus and 

 the pectoralis major, which for this reason some authors have 

 considered as composed of two muscles each; thus the com- 

 mon extensor and flexor muscles of the fingers and toes, though 

 simple at their origin, are divided at their insertion into seve- 

 ral parts. The serrati transversi and other muscles which are 

 attached to the ribs by digitations, are also nearly in the same 

 state. The muscles which have a common origin may be 

 compared to those of this description, as the muscles that are 

 attached to the ischium, as well as those with a common inser- 

 tion, as the latissimus dorsi and the teres major. 



718. There are again muscles the composition of which is 

 different: such are several of the spinal or vertebral muscles, 

 and particularly the transversalis spinse, the longissimus dorsi, 

 and sacro lumbalis; they each result from many muscular 

 bundles, distinct at the extremities and confounded at the cen- 

 tre, in such a manner that each portion of muscle, though sin- 

 gle at one extremity, terminates at the other with two parts; 

 and reciprocally each of the latter is attached to a double por- 

 tion of the opposite extremity: these muscular bundles suc- 

 ceeding each other, and uniting with each other laterally, there 

 results from it a very long muscle, composed of short bundles, 

 distinct at their extremities, and united laterally in their mean 

 part. Each bundle being closely united with the two bundles, 

 can not contract without the latter entering into action at the 

 same time, so that the movement is always communicated at 

 once to several vertebrae or ribs: a disposition altogether in 



