FINDING AND FEEDING CAPOCALA LARV/E. 



(Lulu Berry, Vinton, Iowa.) 



In the spring when the buds begin to swell, I take a peep every morn- 

 ing at my collection of Catocala eggs, in their little tight glass jars, for as early 

 as April seventh I may find the ilias and ultronias hatching. When I discover 

 larvae I put a few twigs of oak in the ilias' jar and twigs of wild cherry, apple 

 or plum in that of the ultronias. The tiny caterpillars soon bore circular holes 

 in the leaf buds. The weather may prevent the eggs of these species from 

 hatching until a month later. 



I think our earliest species of Catocala are clintonii and nubilis, but I have 

 not studied the life-history of either. Unijuga, cerogama, innubens, parta and 

 arnica are also early species, while the larvae of amatrix, cara, relicta, vidua 

 emerge later. The relictas hatch, a few a day, from May sixteenth until well 

 into June, but ilias and cereogamas all hatch at about the same time, which 

 makes it easier to care for them. If the weather is unfavorable, however, a 

 scarcity of the species may result. When much rain falls and the leaves expand 

 rapidly Catocala larvae are liable to succumb to dysentery. Heat is very un- 

 favorable to them, and they prefer a weak light. Many young larvae drown 

 in the moisture which collects on the sides of their jar. "Eternal vigilance is 

 the price of safety," and one can hardly look at the jars too often, not disturb- 

 ing the inmates of course. 



As the larvae grow they must be transferred to larger jars or boxes, for 

 overcrowding invariably produces bad results. After the food-leaves expand, 

 I usually gather them about sundown. In pleasant weather they keep fresh in 

 the glass jars, but in hot weather I wrap the stems in a wet cloth and again in 

 oiled paper. 



Cleaning the jars is, perhaps, best done in the morning, but one should 

 never disturb larvae while they are moulting. Pieces of paper placed in the 

 cages are utilized by the larvae in forming their cocoons. 



I have reared here at Vinton, Iowa, piatrix, neogama, vidua and retecta on 

 walnut and hickory. Palaeogma and piatrix are big spotted fellows, very easily 

 raised from the egg, but I have never found these larvae on their food tree. 

 Neogama larvae, however, may be found almost any day in June on walnut 

 or butternut. Stripping off hickory bark I have found vidua and habilis larvae 

 beneath. 



Lucianas from Colorado and ahohbahs from Utah do well in this locality. 

 I should say that for successful rearing of Catocalae the prime requisites are cool- 

 ness and shade, plenty of food, always fresh; pure air, gained by opening the 

 jars daily, and reasonable cleanliness. Some species — innubens especially — are 

 very liable to escape at pupating time. If only a thin glass plate covers the jar 

 or box, it is well to place a weight on it. 



Concumbens is a fine specimen which feeds on broad leaved willow, as 

 does cara; while parta and amatrix select the slender leaved or white willow. 

 Amatrix also feeds on cottonwood, but I have never found parta upon this tree. 



I never find innubens larvae on their food tree, the locust, but some distance 

 from it, hiding under paper, boards, and the like; while minuta, another locust 

 feeder, is found in the bark grooves at various elevations. 



Fully grown grynea larvae are easily found in crevices of apple bark, 

 ultronias on plum twigs and thorns, especially on dead twigs. The only 

 clintonii larvae I ever found was on plum, May 5, 1913 and as it was in- 



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