SATVIMXAH: OKXKIS SK.MIDKA. 141 



It has hoeii o-ciKM'allv supposed to o('cu])v two years in its transtonua- 

 tions. 



Oviposition. I have made several experiments in ohtaininf^ egijs, but 

 only twiee suecesst'idly. In the first instance a sinii'le eifg was obtained 

 lying upon the ground. In the last, twenty eggs were obtained by im- 

 prisoning females in a laee bag over a pot of growing sedge on the very 

 summit of the mountain. \o eggs were laid upon the sedge itself, but 

 three or four on dead roots and sticks ; most were laid on the netting and a 

 couple on the wire that sup[)orted it. It seems probable that the eggs are 

 laid in nature near the base of the clumps of sedge which stud the plateau 

 thicklv, without regard to whether the tissue on which it is laid be living 

 or dead ;* with all my watching I have never been able to detect the females 

 in the act of laying, but one often starts them up from deep down in the 

 sedge. The eggs hatch in from nine to fourteen days, the exact time being 

 uncertain from not knowing just when the eggs were laid. The females were 

 imprisoned from July 21 to July 27, during most of w^hichtime there was 

 a rasrinff storm. They must have been laid between the 2 2d and the 26th 

 and probably (from the better weather) on the last named day: one 

 hatched the night of August 3-4, two on the 5th, one the 7th, two the 8th, 

 and seven the 9th. 



Food plant of the caterpillar. Nearly all the species of this family, 

 so far as they are known, feed in the caterpillar state on grasses ; but as 

 the true grasses are rare in the inhospitable region where this insect is 

 found, being replaced almost altogether by the allied group of sedges 

 (which are fed upon by at least four species of European Satyrids, of three 

 genera), it is not surprising that this has been found to be the food of the 

 larva of O. semidea. I have previously maintained that lichens furnished 

 them nourishment, because all the living caterpillars I had then found were 

 upon or in very close proximity to one species (Peltigera canina Hoifm.) ; 

 in one instance the animal was apparently feeding upon it ; at least the 

 head of the caterpillar was in juxtaposition to the lichen, and this had an 

 eroded appearance ; but the improba})ility of such a food-plant caused me 

 long since to doubt my conclusion, and I have since re[)eatedly taken the 

 caterpillar feeding upon a Carex which grows there in the greatest al)un- 

 dance, giving the more level portions of the range the appearance of 

 pasturage. The species is Carex vulgaris var. hyperborea, formerly known 

 as C. rigida var. bigelovii. 



Habits of the caterpillar. In emerging from the egg the caterpillars 

 bite a horizontal furrow beneath half or less than half the crown of the egg. 

 through which they squeeze their way ; sometimes they then leave the 

 egg, but at others, perhaps in half the cases, they devour from half to 

 four-fifths the shell. The caterpillars Imtched l)y me remained cpiiet on dead 



*I have seen one of the Europraii spocics of the fields on a stick of tlry wood lying in tlir 

 Coenonynipha (not faptured) lay an egg in grass. 



