THE GENUS HESPERIA. 95 



term " lateral apophyses " to which conclusion no objection can be 

 taken. In carthaini, etc., there are of course no lateral apophyses. 



/. Eefers to the membranous floor of the genital cavity, or that 

 portion of it closing the 10th segment, extending from the 10th sternite 

 to the tip of the uncus (tergite). This membrane is frequently lost in 

 preparing the specimen, but in a considerable number it is more or less 

 preserved. This portion is pierced by the anus (not shown in diagram), 

 it would be near the point marked by /. The rest of the floor of the 

 genital cavity extends from the posterior margin of the 10th sternite to 

 the bases of the clasps (and of course laterally to the ring of the 9th 

 segment), it is pierced by the aedeagus, i, and is membranous for the 

 most part, but has in many species, as in Hesperia, a circle of chitinous 

 material, h, surrounding the exit of the aedeagus, which may best be 

 called the penis-sheath, a name to which it is probably entitled by 

 priority. 



In the diagram is a suture marked //, quite evident also in the 

 photograph (if successfully reproduced), and to be made out in prepara- 

 tions of many species of Hesperia, this is the suture between the 9th 

 and lOfch segments. 



It will be noted that it marks off from the tegmen a portion that is 

 not 9th but 10th segment, and that the dorsal portion of the 10th 

 segment is not merely the uncus, but also a portion of what we have 

 been used to accepting as the solid indivisible 9th tergite. At its 

 anterior termination it may be regarded as opening out mto the mem- 

 branous intersegmental membrane (floor of genital cavity) uniting (or 

 separating) the 9th and 10th segments laterally and ventrally. The 

 claspers are rather complicated organs, but are divisible, as is very 

 usual, into a lower (ventral) section, the valve n, and an upper (or 

 more dorsal) section, the harpe, k, I, vi. The clasp is a combination 

 of two apophyses of the ventral aspect of the 9th segment, which it is 

 desirable to distinguish by separate names, and for these "valve " and 

 "harpe " seem available, and to hold priority, though much confusion 

 has arisen from ignoring the term "harpe" and using the terms 

 " valve " and " clasp " synonymously. In some groups, as in Pierids, 

 the valve is well developed, but it is difficult to say that the harpe is 

 discoverable, in such a case the terms valve and clasp are practically 

 synonymous. 



In Hesperia the harpe is rather elaborate, it consists of a basal 

 portion, A-, which at the line I folds over (or appears to) and forms 

 what looks like another separate piece, this again terminates in a 

 further process, m, called by Rambur the style, which differs consider- 

 ably in different species. Dr. Reverdin appears to extend the term style 

 to include the whole plate that looks like a separate piece, but is 

 attached to the basal portion, k, at the line I. He uses the term 

 " cuiller " (spoon) for the terminal portion of the valve, indicated in 

 the diagram by n, which has in many species a very spoon -like aspect. 



(To he continued.) 



