( 381 ) 



a|iioitl (('. 13), the dorso-lateral ones (it'tcii siibiueJiau; ou tlie stalk the lateral liristles 

 stand generally in the middle of the joint, especially regularly in the species with 

 distinct grooves (f. 10, Neci/ria ■tauiidersi). 



4. PIKIIIDAE. 



It has been noticed by Messrs. Godman & Salviu {Biol. Centr. Amer., 

 Rhojj. II. p. 173) that there are two very different ty])es of antennae in this family, 

 the antenna of the Dismorphimne diverging remarkably and constantly from those 

 of the other Picrid Butterflies. These distingnished Lepidopterists say {I.e.) of the 

 subfamily I Hsmorphiinae : "The structure of the antennae presents the greatest 

 peculiarity. Each of the seven or eight joints forming the distal end of the club 

 have four round depressions surrounding their distal edge, which we take to be 

 sensory pits, a structure more complicated than we have yet found in any other 

 group of the Pieriim.e* though Turias possesses a ventral series of similar depres- 

 sions." There are two inaccuracies in this statement : the Di&morphiinae, have not 

 four but three sensory grooves to each not-scaled joint, and, on the other hand, the 

 ventral series of similar grooves found in Terias is a constantly recurring character 

 of all the Pieritiae (as opposed to Dismor/j/iiinae). 



a. PIERINAE. 



With the exception of the North American genus Nathalis, there is not a single 

 species in this subfamily in which the antennae are without a restricted ventral 

 groove in the middle line of the ventrally not-scaled joints. The groove, which 

 corresponds to the impression found in Kri/ciindai', varies from being circular or 

 almost circular (f. 15, Colias; f. 17, Gonepteryx) to being a narrow channel which 

 traverses the joint from the base to the apex {Anthocharis). Genera like Stalacktis 

 (f. 18) and Nychitona (f. 19), in which the grooves are very wide, occupying on 

 the club the greater part of the ventral surfaces of the joints, lead over to the 

 antennae of the before-mentioned Siithali.^ (f. 20), which are aberrant in so far as 

 the groove extends over the whole ventral surface of the joint — only the distal joints 

 of the club are not scaled^ — and that, owing to the great laterad extension, it has 

 lost the appearance of an impression, its lateral borders being very faintly higher 

 than the bottom of the groove. In most Piin-inai; the grooves are deeper on the 

 stalk than on the club, and deeper in dry cabinet specimens than in live individuals. 

 In some cases the grooves on the club are very slightly impressed, but they are 

 always traceable, especiallv by the tine sense-hairs. These sense-hairs are generally 

 very short au'd rather broad, having the aiJpearance of minute scales rather tlnm of 

 hairs, and stand closely together in the groove, forming often a rounded silvery 

 patch. 



The sense-hairs are restricted to the grooves, a chwacter by which Pierinae 

 are well distinguished from Kri/cinidae. The grooves seldom occupy the whole of 

 the not-scaled ventral area of the joints; the remaimler of this area is covered with 

 setiferous punctures, which are likewise found on the not-scaled dorsal surface 

 and are especially conspicuous in forms with nearlv naked antennae {Me.fapia, 

 figs. 21,22). 



• riic Picrliuu of Messrs. Uodiuiiu Ac .Salvia, who treat these Butterflies as a subfamily of Papilio- 

 nidae, are our Pieridae. 



