Sexual Dimorphism in the RiUclid gcmis Parastasia. 493 



the shape of a mulberry leaf on the thorax, the scutellum 

 and the sides and extremity of the elytra black. The 

 pale variety may be due only to immaturity, for the species 

 does not seem to be a variable one. The apparent rarity 

 of the female accounts for its having remained hitherto 

 unknown. P. inarginata has been recorded only from 

 New Guinea but was collected by Wallace also in Mysol 

 and Waigiou. 



The type of the last section of the genus (the " hicolor " 

 group of Dr. Ohaus) is P. Westwoodii, Westw., the sexes of 

 which differ only in the remarkable character referred to 

 above, which is common to the whole group. In the male 

 the tarsi of the second pair of legs are very much thickened 

 and shortened, the last joint is extremely large, and the 

 inner division of the outer claw is expanded into a broad 

 blade. This structure was described and ligured by 

 Westwood, who did not observe however that the inner 

 side of the last joint is strongly hollowed out and that 

 there is a strong projection from the inside margin of the 

 preceding joint which meets the lobe of the claw. The 

 whole modification thus forms a perfect hollow grasping 

 structure. Such a modification of the middle tarsi is 

 highly remarkable and makes this division of the genus 

 the most distinct of all, and did not the constancy of many 

 essential characters in all these insects render it most 

 natural to retain them all within a single comprehensive 

 genus the present group might be generically separated 

 with much more reason than those forms which I have 

 merged into the large genus. 



This section constitutes the old genus Ca^lidia briefly 

 characterised by Burmeister from a still undescribed 

 species in Dejean's collection supposed to be Australian. 

 The original specimen labelled " Cselidia quinquemacu- 

 lata, hab. in Nov. Holl." is now in the British Museum 

 and proves its association with nigromaculata, Bl., in the 

 Munich Catalogue to be entirely erroneous. A similar 

 male specimen m the British Museum was collected by 

 Dr. Horsfield in Java, and M. Oberthiir possesses the 

 female from the same island. Both Dejean's locality and 

 that cited by Gemminger (New Guinea), probably by way 

 of improvement, are therefore no doubt wrong. To clear 

 up the confusion I shall describe this insect under the 

 name given to it by Dejean. 



