PINE BUTTERFLIES. 763 



ber is both denser aud more valuable than in that under consideration. Whether it 

 occurs in the Coast Range in Washington Territory I do not yet know, although we 

 might expect its presence, as the Cascades oflfer a similar vegetation, as well as from 

 the general similarity of the Rhopalocerous fauna on both sides of the great Colum- 

 bia Plateau, as evidenced by the occurrence of the same species of Pieris, Colias, 

 Argynnis, Satyriis, aud Pajnlio. The area actually visited where serious damage has 

 been already committed extends about twenty-five miles north and south, with an 

 unknown width, and in this region all the yellow pines have been nearly or totally 

 stripped of their foliage, as well as many of the smaller species of Coniferce. 



The appearance of the forei^t is peculiar. The first impression was that fire had 

 scorched the tops of the trees, so brown and withered did they look in their clothing 

 of dark, blackish moss ; and before the cause of this eflfect was discovered, it was only 

 by persistently remembering that all the large fir trees were green that the idea 

 could be kept out of the mind. 



Life history. — Unfortunately we were only able to study the insect for about seven 

 days, or from July 22 to 28, inclusive. During this period we witnessed the pupa- 

 tion of the first brood, the emergence of the imago from this brood, and the deposition 

 of the eggs. Whether these eggs will hatch this season or remain as eggs until next 

 spring we do not know. If they do hatch, as is probable, the larvae will be innumera- 

 ble and produce wide-spread devastation. Neither do we know at what period the 

 butterflies appeared in the spring, or whether they appeared at all. From analogy 

 there ought to have been a spring brood, of which we found the descendants ; but if 

 so, they do not appear to have specially attracted the notice of the scattered settlers, 

 although they observed great numbers last year during the summer. It is therefore 

 evident that, so far as observations in this part of the country are concerned, there is 

 yet much to be learned. All parties, however, who were questioned on the subject 

 agree that the season of 1881 was the first in which the abundance of the pests was 

 such as to cause general comment, the opinion being often expressed that it was not 

 previously known, although this is evidently erroneous. As the winter of 1880-'81 

 was exceptionally severe and peculiar in someof its meteorological phenomena, it be- 

 comes of importance to solve the query whether the sudden increase of this species 

 was due to peculiar climatic conditions which destroyed great numbers of its para- 

 sitic or other enemies without impairing its own vitality. Certain it is that the 

 silence of the forest was most remarkable, the absence of birds being specially noticea- 

 ble, while bats were more than rare throughout the whole region traversed by our 

 party, on both sides of the great i^lateau. 



Habits of the imago. — The perfect butterfly, when just out of the chrysalis, is one 

 of the most beautiful but at the same time most delicate of its race. It is fragile in 

 the extreme, and soon loses its freshness from its habit of creeping into and between 

 the pine needles in search of the female, or for the purpose of laying its eggs. Great 

 numbers must perish accidentally in high winds ; indeed, dead or damaged ones were 

 plentiful in the dust of the roads. Copulation takes place almost directly after 

 emergence, often before the wings are fairly dried ; sometimes the male being as fresh 

 as the female, sometimes old and worn. The average duration of life is probably 

 very short, and in this connection it would be interesting to ascertain whether the 

 worn males first seen were relics of the first brood or exceptionally early stragglers 

 of the second. 



The egg, — Examination of the abdomen of a female just after copulati<m disclosed 

 49 well-formed eggs. Search for eggs on the terminal needles disclosed them in 

 groups ranging from 3 to 22 in number, deposited in a row on the needles, the eggs 

 not being set upright, but at an angle of about forty-five degrees, overlapping each 

 other like shingles, and apparently thoroughly cemented together. Those found 

 were on young trees which had not been touched by the first brood of caterpillars. 

 A female found in copulA in the morning was imprisoned about 2 o'clock on a pine 

 fascicle, and by six o'clock had laid 16 eggs in. a continuous row. These were pale 



