rilK BUTTERFLY: INTERNAL ORGANS. 51 



by it at its starting- point, at the entrance of the cord into tlie aljdonien, 

 which might easily l)e taken for a ganglion. 



Glandular system. It is stated hy authors that a j)air of ramose 

 glands is sometimes found in the female hutterfly, situated near the orifice of 

 the vagina, "which secrete, perhaps, an odorous substance that excites the 

 copulatory act." They are noted in Melitaea and Argynnis, and I once de- 

 scribed from the dissection of the nearly mature female pupa of .Vnosia '*a 

 transverse reniform vessel, attached broadly by its base to the inferior wall 

 of the oviduct at its very extremity," its tip terminating in two little threads. 

 But as Burgess made no note of any such organ, the ])oint requires new 

 dissections to establish it. These glands nmst not be confounded with those 

 opening externally in the female of some butterflies, noticed abo\e. 



Reproductive system. The paired ovaries of the female consist each 

 of four tubular branches which at maturity are longer than the body of the 

 insect, and always so long that they have to run backward and forward, 

 sometimes many times, to accommodate themselves to their narrow quarters, 

 often rolled over and over, but always connected by their united and now 

 solid tips to the u[)})er wall of the abdomen, — in .Vnosia at the fourth scu- 

 ment. From their tips backward the ovarian tul)es increase in size and 

 contain each a hundred ovigerous cells more or less, in which the bases of 

 the future eggs lie outward. As they attain their largest the four ovarian 

 tubes unite on each side to form an oviduct, and the two oviducts shortly 

 afterwards unite to form a common duct, the oviduct proper, Avhich is the 

 common receptacle of all the special accessory organs, and itself is often 

 enlarged in some Lepidoptera to form a point of arrest for the ego's while 

 they are prepared for future needs. The most important of the ort>-ans 

 tributory to the oviduct are those which enter it near the middle by the 

 sperm duct — a slender tube connected directly with a vescicular sac, the 

 s[)ermatheca, which by a similar tube at its opposite extremity is joined to 

 the large, long- oval, bladder-like, but muscular capsule, the copulatory 

 pouch ; this conducts by a larger tube or curved canal, the vagina, into 

 the vestibule on the tmder surface of the seventh and eighth seo-ments. 

 There also enter the oviduct two sets of accessory glands, one single, 

 morphologically the mate of the spermatic vessels and the smaller, the 

 other set paired, and all consisting first of filiform secretory vessels, next 

 of a reservoir and last of a short excretory duct Avhich opens into the o% i- 

 duct ; their function is supposed to be connected with the final prepara- 

 tion of the egg wall and its varnish-like coating. The ovipositor is formed 

 of the lateral lappets of the ninth segment. 



The male organs consist of a single large globular testis, compound in 

 origin but now simple in structure and homogeneous, often highly colored, 

 rose, green or purple, mesially situated in the fifth abdominal segment 

 (or just about the centre of the abdomen) above the stomach. It is retained 



