180 MR. LUBBOCK ON THE CUTANEOUS MUSCLES 



No. 63 rises partly under the fore end of 7 and partly between 7 and 1, and passes 

 backward and dowTiward to the upper end of 49. 



No. Gh rises mider 7, and jvist on the lower side of 63, and runs parallel to that muscle. 

 It does not however pass so far back. It is generally completely double. 



No. 65, again, rises just below 64, and passes back parallel to it, but is about twice as 

 long, and reaches to the upper end of 42. 



No. 66 rises under the posterior end of 17, and passes forward and upward to the 

 posterior end of 64. 



No. 67 rises on the lower side of 42 and passes upward to the fore end of 66. 



No. 68 rises under the lower end of 49 and passes forward and upward to the anterior 

 end of 8. 



No. 69 rises at the fore end of 68 and passes to the lower end of 50. 



No. 70 rises at the huider end of 68 and passes to the hinder end of 40. 



No. 71 rises at the lower end of 70 and passes to the upper end of 54. 



No. 72 rises at the hinder end of 63 and passes to the lower end of 60. 



No. 73 rises under the middle of 17 and passes downward and forward to be inserted 

 close to 24. 



No. 74 rises at the upper end of 73 and diverges from it toward the upper side of the 

 lower end of 66. 



No. 75 is behind, and almost parallel to, the preceding. 



No. 76, rising under the fore end of 8, passes backward and downward to be inserted 

 under the middle of 17. 



No. 77 rises at the posterior end of 76, under 17, and passes straight back to the hind 

 end of the segment. 



No. 78 also rises at the hind end of 76 and passes downward and backward. It is a 

 short and small muscle, consisting generally of four distiiict'fascicles. 



First cmd Second Thoracic Segments. — The muscles of the thoracic segments differ from 

 one another, as might be expected, much more than do those of the abdomen. It is 

 unnecessary here to mention the muscles which agree with those of the third thoracic 

 segment, and I will therefore confine myself to pointing out the differences, using the 

 third thoracic segment as the standard of comparison. 



Second Thoracic Segment, however, does not differ very much from the third, and this 

 agreement is even more striking in the small muscles than in the large ones. 



Nos. 4 and 7 are thinner and weaker. 



The single muscle representing 10 and 11, which are again distinct in the first thoracic 

 segment, is here expanded in front, and usually double. 



Nos. 16, 19 and 20 are represented by only two muscles. 



No. 18 is double at the posterior end. 



No. 22 rises at the upper end of 16, and passes backward and upward to the posterior 

 end of 6. 



No. 52 runs from the lower ends of 50 and 72 to those of 64 and 55. 



Nos. 67 and 58 in most of my specimens had united together, and were smaller than 

 in the third thoracic segment ; but this is not, I presume, always the case. 



