145 Was Joyous and Beautiful. and As I Sit with Open Box Before Me
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THE CANADIAN ENTOMOLOGIST 145 was joyous and beautiful. And as I sit with open box before me and listen to the sleet driven from out the winter darkness against the window panes, I dream of June vacation days-the scent of spruce and fir arises and I gaze across the logs through shimmering heat waves to the cool shadows of the clustering pines. NEW LIFE HISTORIES IN PAPAIPEMA SM. (LEPIDOPTERA.) BY HENRY BIRD, RYE, N. Y. (Continued from p. 115). Papaipema speciosissima G & R. A thirteen-year search for the larva of this species, one of the few eastern ones remaining unknown, culminated successfully in 1913. By reason of its fine coloration and large size the species was well known as a moth, even though but few exan~plesever found a way into collection. At the time of the description in 1868 (Trans. Am. Ent. Soc., Vol. I, 342), Grote and Robinson relate receiving their type from Seekonk, a suburb of Providence, R. I., and an accompanying figure made its individuality clear. Thirty years later Prof. J. B. Smith found "perhaps a dozen fernale examples" in the aggregate of the principal American collections which he perused when writing monographically of the genus. While known to be generally scattered over the north-eastern United States, most of the examples coming to light of late years bore the label of northern Kew Jersey. As the establishment of the preferred food-plant through a painstaking search has brought out a bearing of primitive conditions on the result, it may be helpful to relate details. It was conceded the larva would have a boring habit, its large size would indicate the occupation of some stocky stein or root, so this problem of isolating the food-plant was the first question, and one beset by certain ecological features. So long ago as 1900 the writer visited the type locality in hopes of meeting some plant peculiar to that section which might furnish a clue to the desider- atum. Obviously, one way of getting an idea of a !ikely plant for investigation would be to visit a number of places \\-here the May, 1915 146 THE CANADIAN ENTOMOLOGIST moth had occurred, compare the floral conditions, and note the suitable plant forms common to such stations. Working on these lines many stations from Montreal, Can., to Wilmington, Del., were visited, but the results led nowhere. What did appear was that the great semi-tidal marsh westward of Jersey City and Hoboken, S.J., yearly gave up a few of the moths, and made it apparent an established colony must be flourishing in these fastnesses. The flora of this region is of the usual luxuriance of an ancient marsh, though modified by a considerable salinity in its lower reaches. Very conspicuous are a number of giant grasses, Phragmites phrag- mites, Spartinu cynosuroides, Zizania aquatics, and others, which are capable and fit to serve as food-plants. For many years we laboured under the impression that some of these grasses must be the answer to the riddle. A number of large herbaceous species also occur and the field for investigation was a large one. From a contemplative viewpoint this habitat offers much to be desired. Many of the floral conditions here have seen little change in the last piling up of centuries, certain sections remaining doubtless in their pre-Columbian verdancy, and we should, theoretically at least, find our larva easily. But the proximity to so great a popula- tion has produced much artificiali~yand the region is interspersed by numerous railroads that are responsible for frequent burnings. The principal hinderance to a thorough search, however, is the fact ' that the territory is wet to submergence except during very droughty times. Our meeting with the larva of P. inquesita in a Cryptogam, in 1898, made us early mindful of the ferns, though the food- plants of the genus centre principally among the Composites. Light dawned in 1912 when P. stenocelis proves a fern feeder, for inquesita, stenocelis and speciosissima are a trio aloof from the allies, and it becomes clear we must now also look for the latter in a fern. But what fern was peculiar to the Jersey Meadows? Early in 1913 we found a young borer at work in Aspidium, at Rye, but the instance did not reflect a normal operation for our desider- atum. Latterly, Mr. Otto Buchholz, of Elizabeth, N. J., had rendered assistance in the Jersey Meadow hunt, being close by the field, and keen, through a wide experience and with a skill rarely equalled, for detective work of this nature. Upon being advised THE CANADIAN ENTOMOLOGIST 147 the search had narrowed down to the ferns, with usual acumen, he soon located the great colony of the Meadows. It developed the common Osmundas are the ones chosen, both 0. regalis and 0. cinnamomea being infested. Whether 0. claytoniana is also bored did not develope, since that species did not occur here, being a denizen of dryer places. While it is a surprise this common fern proves the food-plant so long sought, Osmunda regalis being the favourite, and that negative results had followed its examination in hundreds of cases previously, the prominent feature is the localized colony encountered, with the evidence of its probable antiquity. From twenty years' observation on the growth of Osmunda under our windows, we do not hesitate to state that most of these individual plants represent fifty years development at least. The gnarled, ruminating root-stocks are elevated 50 to 60 cm. above the level of the quaking morass, in the effort to get above the water and from the nature of the yearly accumulations, and show the borings of preceding generations. The presence of the larva in 0. regalis is not easily noted. There is no wilting or drying of a collspicuous frond as happens with the other fern borers. The newly emerged larva enters a miniature stipe whose uncoiled, tender tip has sprung up but three or four centimeters, and in a few days has tunnelled down into the root-stock. This dies, it is true, and is some evidence, but a peculiarity with this fern in this locality seems to be that many more fronds start than eventually mature, what appears to be a fungous blight nipping some in their tender incipiency. Further, a dipterous larva bores these young stipes and causes them to die, so that we find two other similar results produced at the same time in the plant, as is occasioned by the working of speciosissima. As the larval period lengthens, the frass thrown out is the only indica- tion, and this is not in the usual well-formed pellets, but a rusty- brown, mud-like deposit. Even this sign is hard to detect for the fruiting fronds send down their brown inflorescence, which, with the chaff-like scales from the stipes sprinkle the root-stock and help to smother the meagre clues. So the apprehension of this larva is not as easy as with most others, and the surprise greater, when, at maturity, one of these old roots is cleft open, disclosing 148 THE CANADIAN ENTOMOLOGIST - a pair often of great pink larvze which have their whereabouts hidden to such a remarkable degree. The last week of May can be assigned as the date of general emergence from the over-wintering egg, and maturity is reached about Aug. 1. It did not develope that there was the usual amount of parasitism from the smaller hymenoptera that work so assidu- ously against most of the allies about the fourth instar, and only Ceromasia myoidaa seemed to assail the last stages, but this Tachinid was a prevalent check. The following brief tabulation, except for the first instar, may sufficiently place the larva: Stage 11.-Generically typical, of the group with dark purplish- brown girdle which is not crossed by the white lines; head shows side line; tubercles well developed but not large, blackish, IVa absent on joint ten. Head and cephalic shield concolorous, dorsal and subdorsal lines whitish and broken at girdle. Stage 111.-Colour unchanged, tubercles not prominent, except on joint eleven 111 and llla are fused into a large plate greater than the spiracle and the latter somewhat larger than the anterior ones, and on twelve I and I1 are of the usual prominence. Stage 1V.-Head has lost dark line at ocelli, is chestnut brown; the cephalic shield is as wide as head, yellow, margined laterally with a black border; lines white and conspicuous, the girdle becomes a shade paler; tubercles the same. Stage V.-Colour changes to a pinker tone, otherwise similar; the fused 111 and IIIa on eleven remain the largest of the lateral plates, which on the whole are small. Penultimate Stage.-Colour is pronounced pink, the trans- lucence at the sutures giving a ringed appearance, the white lines are nearly lost except the dorsal on the thoracic joints; tubercles and spiracles black, the former reduced; 111 and IIIa have separated on joint eleven. Maturity.-A robust larva with prominent brown head, cephalic and anal plates, the tubercles except I and I1 on joint twelve inconspicuous; IVa has never developed on joint ten, and on eleven 111 and IIIa still more separated, the former the largest lateral plate; IV never gains its usual prominence as occurs with THE CANADIAN ENTOMOLOGIST 149 most other congeners. The colour is a pale pinkish hue, and with the large size is productive of an individuality pronounced with this species. Length, when full grown, 50 mm.; breadth, 7 mm. The gallery is abandoned for pupation, dates Aug.