CHAPTER V. 



O^ THE ANATOMY OF ALETIA. 



By Charlbs Sedgwick Minot and Edward Bubqess. 



[Plates VI-XI.] 



The following chapter was prepared at the request of Professor Eiley, 

 to whose kindness we are indebted for the material upon which our 

 observations have been made. Several untoward circumstances have 

 contributed to interfere with the progress of the investigation. The 

 work was begun by Dr. Minot, who was subsequently joined by Mr. 

 Burgess, in the hope that our joint labors would prove more efi&cient. 

 Nevertheless we find it necessary to leave various points undecided. 

 This incompleteness is partly due to the unavoidable imperfection of 

 preserved specimens,* and partly to the scanty light yet thrown on insect 

 anatomy and physiology. 



ANATOMY OF THE LAEVA. 



The external anatomy of the larva need not be again described in 

 this chapter. There are only a few points to be noted in regard to the 

 legs, the previous descriptions of which are somewhat incomplete. The 

 true legs, Plate YI, Fig. 4, are conical, three-jointed, and provided with 

 a terminal hook. Fig. 6, which is curved toward the median line of the 

 body, and has at its base a thick swelling, usually described as a fleshy 

 pad; the adjective fleshy is hardly appropriate, as the pad is covered 

 by a well-developed, hard crust. There are two hairs on the first joint, 

 the lower being much the slenderer. There are four hairs on the lower 

 part of the second joint, two on the inner edge rather stout and curv- 

 ing, and one fine one just below them, and a long one in front. On the 

 last joint again are four hairs, all near the terminal claw, namely, a 

 small one in front, a thick, curving one on the side, another thick, curv- 

 ing one just above the pad of the claw, and immediately above this the 

 fourth hair, which is shaped something like an Indian club, and is ap- 

 parently somewhat flattened. The constancy of form and disposition 

 of these hairs lead us to think that their arrangement must be of some 

 importance, therefore we have given this detailed description. 



* Some material preeerred In a 5 per cent, aolntion of chloral-hydrate was found very naefoL With 

 this pregerrative, spocimens should b© opened in •everal places to allow the fluid to penetrate into the 

 interior. Inde«d this shoold be done with alcoholic speoimena also. 



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