253 



ON THE EGG-LAYING AND EARLY STAGES OF 



HESPERIA LINE A {= THAUMAS), 



By F. W. Frohawk, M.B.O.U., F.E.S. 



(Plate VIII.) 



After repeated attempts to obtain the eggs of Hesperia linea 

 from captive females, I determined, if possible, to watch this 

 species depositing in a state of nature, not only for the purpose 

 of securing eggs, but to ascertain the cause of so many failures 

 in trying to get them to lay in captivity. I therefore, in com- 

 pany with my friend Mr. Ed. Goodwin, visited a certain locality 

 on the Kentish Hills, where this butterfly is abundant, pn July 

 17th last, purposely to make observations on this species, and 

 to collect the larvae of Lycana minima. After watching Hesperia 

 linea for a short time, we soon had the satisfaction of seeing 

 three females deposit between 3.45 and 4.30 p.m., and found the 

 eggs of each. To lose no opportunity I made a sketch on the 

 spot of the first female we saw in the act of depositing, the 

 drawing of which is reproduced in the accompanying plate. 



The two species of grass selected by the butterflies for their 

 eggs were cat's-tail grass {Phleum pratense), and soft creeping 

 grass {Holcus mollis). All three females went through precisely 

 the same performance and mode of depositing. After flying 

 with a slow, steady, buzzing flight in and out among the taller 

 stems of the mixed grasses growing in a dense mass of varied 

 herbage in a wild uncultivated sheltered slope on a chalk hill, 

 the butterfly now and again settled for a moment on a grass- 

 stem, but obviously not suited for its eggs, would quickly fly off 

 and settle on another, if suitable ; she would settle on the upper 

 sheath, and immediately slide down tail first, and at once start 

 feeling for the division along the sheath with the ovipositor, 

 working partly or wholly round it, and slowly crawling upwards 

 during the process until it found the exact place to suit its 

 requirements, in the choice of which it seemed very particular ; 

 it then rested with its wings closed over its back, antennae 

 lowered in a line with its body, and the abdomen curved, with 

 the extremity closely pressed on, or just in, the crevice of the 

 sheath, and the ovipositor deeply inserted. In this attitude she 

 remained for three or four minutes, when I sketched her. While 

 thus resting she laid four eggs in a row along the inner surface 

 of the sheath opposite the aperture, quite hidden from view. 



After watching this one we noted both the other females 

 behaved precisely the same in their actions. The first one laid 

 four eggs, the second three, and the third one three ; but I found 

 six were laid close together in one sheath, but afterwards these 

 proved to be the eggs of two females, as three of them hatched 

 several days in advance of the others. It appears that the 



ENTOxM. SEPTEMBER, 1912. X 



