180 . MR. LUBBOCK ON THE CUTANEOUS MUSCLES 
No. 68 rises partly under the fore end of 7 and partly between 7 and 1, and passes 
backward and downward to the upper end of 49. 
No. 64 rises under 7, and just 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 hinder 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 50. 
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 56. 
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. Å 
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 distinct fascicles. 
First and 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 
endof6. X à 
No. 52 runs from the lower ends of 50 and 72 to those of 54 and 55. 
Nos. 57 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. 
