78 KANSAS UNIVERSITY QUARTERLY. 



present in the wing substance, and Prof. Mason B. Thomas* has 

 demonstrated the existence of glands in the wings and their direct con- 

 nection with the androconia in Danais archippus, Thecla calamus, et al. 

 Under such a condition the scent-stuff passes up from the gland 

 through the pedicel of the androconium, and is dissipated from the 

 feathery tip or the scattered lateral openings of the scale. 



The specialization of androconia is therefore a distinct modification 

 of the scale or hair. The scarcity of the scent-scales, however, 

 compared with the ordinary scales, and their ease of recognition 

 renders them but little likely to confuse the student endeavoring to 

 discover the state of specialization of the general wing-covering of a 

 lepidopteron. Their presence, however, it must be noted, is often 

 accompanied by a specialized development in size and shape and 

 arrangement of a considerable number of the ordinary scales adjacent 

 to the androconia and serving to protect or conceal the scent-scales. 

 The very large scales overlying and concealing the androconia along 

 the cubital and anal veins of the forewings of Argyn?iis idalia, and 

 the large assurgent scales often noticeable in the androconia-bearing 

 patches or spots of Hesperids are example of this. 



Scent-organs are also known on the bodies of Lepidoptera, espe- 

 cially among the moths. Von Reichenauf finds the privet and pine 

 hawk-moths to be provided with a special scent-organ at the edge of 

 the lower side of the first abdominal segment; it comes into view on 

 pressure of the abdomen of the dead or living insect, and consists of 

 two symmetrical bunches of hair-shaped scales, which may be 

 extruded or drawn in. When they are extruded in a living Spliinx 

 ligustri a distinct musky scent is apparent at the distance of half a 

 meter; but ceases to be apparent when they are retracted into their 

 fold, which occurs when the insect is at rest. Only a rudiment of 

 this organ is present in the female. 



Prof. P. Bertkau| has studied the scent-organs of various German 

 Lepidoptera. The Noctuina have ventrally placed organs of the 

 Sphingid type. In Hadena and Dichronia the hairs of the tuft are 

 extraordinarily long; there is not, as in the Sphingidse, one scale on 

 one large gland-cell, but several smaller cells belong to one scale. 

 A very similar apparatus was found in some Orthosiidse. 



Scales probably subserve still another function, namely, that of 

 producing sound by stridulation. According to Haase certain hard 

 scales on both sexes of the Indian genus Hypsa appear to produce a 



♦Thomas, Mason B., The androconia of Lepidoptera, American Naturalist, vol. 27, no. 

 3'23, p. 1018, November, 1893. 



+Von Reichenau. W., Kosmos, IV, 1880, p. 387; "abstract in Jour. Roy. Mlc. Soc, series 

 1, vol.III, p. 938, 1880. 



tBertkau. P., Verh. Nat. Ver. Preuss. Rheinlande, XLIV, 1887, pp. 118-119; abstract in 

 Jour. Roy. Mic. Soc, series 2, vol. 8, p. 406, 1888. 



