8 • DONALDSON BODINE. 



Of the various antennal organs which have a communication with 

 nerves, and are therefore presumably organs of special sense, I shall 

 describe six kinds : 



1. Short, slender, pointed sense-hairs which are hollow, but closed 

 at the free ends ; Fig. 23, 1 , shows these in their relation to the rest 

 of the antenna; Fig. 13 represents a section magnified about 500 

 diameters. The hair is attached to the chitinous ring at the end of 

 a pore-canal. It has been described as movably articulated, but 

 there is no muscular tissue connected with it as with the hair of 

 ^[ammuls. The elasticity of the connecting zone of chitin may 

 allow a certain amount of flexion and of subsequent extension, but 

 it can scarcely be said to be movable in the active sense. In the 

 specimens I have examined the external part of the hair does not 

 exceed 45 m. in length, and it is usually more or less flexible. From 

 the interior a fibre from a branch of the antennal nerve passes out 

 into the cavity of the hair. Ruland* says the question whether the 

 nerve, ascending through the pore-canal to a ganglioual swelling, 

 ends in the base ; or whether it sends up a modified continuation 

 into the interior, is not yet settled. He is unable to decide to his 

 satisfaction. Some of my preparations seem to me to show clearly 

 that the nerve itself extends some distance into the hair. Just entad 

 of the hair Hes a large nerve-cell. It is more or less ovate in form, 

 with the smaller end produced into the pore-canal. It contains from 

 three to six nuclei, which are coarsely granular in apjiearance. Au 

 " axis-cylinder" is clearly visible in the apical part of the cell, but 

 it fades from sight toward the middle. 



This ty})e of sense-hair has a wide distribution. It occurs very 

 generally in both the Jugatic and the Frenatie. Mr. Scudderf says 

 that in no instance has he observed the antennae of the butterflies 

 clothed with hairs. He doubtless refers, however, to hairs of a dif- 

 ferent type described below. Those of the fir.st kind are more or 

 less abundant in many forms. 



2. Long, very stout and rigid bristles or hail's, closed at the end ; 

 Fig. 14 represents a section of one from a nuile 1 1 Ioshdi ia p romet liea. 

 These are easily recognizable by their thick l)a.<<' and tapering form^ 

 and also by their characteristic insertion. They have a distinct, 



■■ Beitrage zur Keimtniss der Anteniialen Siuiu'sorsiane der Iii.sekteu, Franz 

 Rulaud, H:iinl)iirg. Zeit.schrift fur wissenschaftliche Zoologio, vol. xlvi. pp. G02- 

 628. 



t Buftcrtiius of Eastern United States and Canada, vol. i, p. 37. 



