176 MR. LUBBOCK ON THE CUTANEOUS MUSCLES 



segmeut, passes upward, with a slight inclination backward, dividing at the same time 

 into two heads, which are inserted on the ventral side of 2, and nearly opposite the an- 

 terior attachment of 1. 



No. 36 (part of d of Lyonet) is parallel to the preceding and has similar attachments, 

 but lies rather further back. 



No. 37 (part of a of Lyonet) rises under the fore end of 16, and running forward and 

 upward is inserted under the middle part of 35. 



No. 38 (part of a of Lyonet) bears the same relation to 36 that 37 does to 35. 



No. 39 (part of I of Lyonet) is attached under the fore end of 19, and passes backward 

 and upward to be inserted iuto the trachea close to the spu-acle. 



Nos. 40 and 41 {m of Lyonet). These two muscles rise anteriorly under 20, and pass 

 diagonally backward and upward for about one-third of the length of the segment. 



No. 42 (« of Lyonet) is parallel to and on the ventral side of the preceding. 



Nos. 43 and 44 rise on the dorsal side of 28 and pass backward and upward along the 

 posterior margin of 42, opposite to about the middle of which they are inserted. 



No. 45 (part of I of Lyonet) may perhaps be regarded as a continuation of 39. It is 

 inserted into the posterior and lower side of the trachea, close to the spiracle, and passes 

 backward and upward to be inserted close to the upper end of 49. 



Nos. 46, 47 and 48 {(i of Lyonet). These three transverse muscles lie on the outer side 

 of the following, and are therefore covered by it in the drawing : 46 and 47 are usually 

 joined together at the upper end. With the two following they are concerned in the 

 movements of the proleg. 



No. 49 (y of Lyonet) is attached below the proleg, and passing upward to the inner 

 side of the preceding, is inserted just above it. 



No. 50 also is attached at its lower extremity to the proleg, and, passing upward and 

 backward, is inserted under the great lateral trachea. 



No. 51 (8 of Lyonet) ought almost to be considered as two muscles, since, though it 

 rises singly close to the anterior end of 34, it divides almost immediately. Both branches 

 pass upward, inclining at the same time, and especially the posterior branch, backward, 

 to be attached under 6. 



No. 52 (e of Lyonet) is a short transverse muscle which lies altogether on the outer side 

 of the anterior branch of 51. 



No. 53 (r of Lyonet) rises at the lower end of 48, and passing straight down, at the same 

 time expanding in width, enters the proleg. 



Under this muscle lie four other small ones, which also are attached to the proleg by 

 theii" lower ends. 



No. 54 (perhaps part of i of Lyonet) is a transverse muscle which lies on the outside of 

 31 and 32, and partly of 28 also. This muscle and the following are often difficult to 

 find, from their being covered by the skin-fold. 



No. 55 (perhaps part of t of Lyonet) is in this segment generally completely double, and 

 lies parallel to and just behind the preceding. 



No. 66 is a series of about eight ti'ansverse muscular fascicles which lie on the outside 

 of 28, 29 and 30, and are much hidden in a fold which is bounded by the ridge already 



