194 



Garden and Forest. 



|NUMBER 482. 



too, in a hundred good varieties, are cultivated in commercial 

 nurseries. The brilliant and imposing Torch Lilies, or Red- 

 hot Poker-plants, are varied in size, the dwarf Kniphofia 

 MacOwani having spikes two feet high, while the torches of 

 the giant K. nobilis are higher than the head of a man, with 

 other sorts of intermediate height. The profuse and enduring 

 flowers of Japanese Anemones last until they are whipped to 

 pieces and scattered by winter winds. With all these and 

 Chrysanthemums, Crocuses and many more, the autumn gar- 

 den may be distinct from the garden of other seasons, and 

 have a character of its own which will be individual and fresh. 

 A garden to be interesting need not have long ranges of 

 glass. To be sure, cheap glass has brought within the range 

 of modest means the growing of delicacies for the table and of 

 flowers for home use. But the range of plants cultivated 

 under glass does not compare with the numberless hardy 

 ones collected from the north and the south temperate zones 

 and from mountain ranges, not to speak of those acquired 

 by hybridization. Cheap glass has had the effect of directing 

 attention away from outdoor cultivation, and too often hardy 

 perennials are spoken of slightingly. The brightest and most 

 interesting garden that I know, and which is a changing picture 

 during nine months of the year, has no glass house, and is a 

 forceful plea for the satisfaction and success of the hardy 

 flower garden. , 



Madison. N.J. A. Hemngton. 



Entomological. 

 The Plant house Aleyrodes. 



ALEYRODES VAPORARIORUM was described by Pro- 

 fessor J. O. Westwood in The Gardeners' Chronicle for 

 1856, page 852. Its occurrence in America was not re- 

 corded until over thirty years later, and it seems probable 

 that the species was in some way introduced into America 

 from Europe. Inasmuch as it is now found in such widely 

 separated localities as Michigan, Kentucky and Connecticut, 

 we may well suppose the insect to be well distributed, at 

 least, over the north-eastern portion of the United States. 



This Aleyrodes is found upon Strawberry-plants in the 

 garden, but it is more especially in the greenhouse that the 

 insect assumes the nature of a pest. The Tomato yet 

 remains the chief host-plant of the parasite, though I have 

 observed the larvae upon the leaves of the Cucumber, Po- 

 tato and Lettuce growing under glass, while among orna- 

 mental plants, Ageratum Mexicanum, Abutilon, sp., and 

 Maurandya scandens were attacked. It has also been 

 reported as infesting Roses, Geraniums, Coleus and Salvia. 



Toward the end of the season the Aleyrodes is most 

 abundant in the Tomato-house, and vast numbers of 

 adults are often seen flying about the tops of the plants, 

 near the glass, where they are mating and laying eggs. 

 On the under surface of the leaves are the silvery white, 

 bristly larva:-, which are without power of locomotion, 

 except when newly hatched, and they subsist by sucking 

 the juices from the plant. 



The egg is oval and slightly conical in shape, with the 

 larger end fastened to the under surface of the leaf. Two 

 females were observed ovipositing upon Lettuce. The 

 beak was first thrust into the leaf, and, depositing an egg, 

 the female swung about, with beak still inserted in the 

 tissues of the leaf, and serving the purpose of a pivot, con- 

 tinuing to deposit eggs in a circle of about one m. diame- 

 ter. One circle contained six, and another nine eggs. 

 Eggs are not always deposited in circles. I have fre- 

 quently found them single and promiscuously scattered 

 over the surface of the leaf. They are of a light green 

 color at first, but soon change to a rather dark brown, and 

 hatch in eleven days. 



The young larvae move about for a short time, during 

 which they find a suitable place to insert their tiny beaks, 

 so that they, too, can suck up the vegetable's juices for 

 their sustenance. They are there permanently fixed until 

 the adult stage is reached. The larvae are nearly white and 

 more or less transparent, with the edges and dorsal surface 

 well covered with shining bristles. When the larva is full 

 grown it becomes a pupa without visibly changing form ; 

 a little later the skin cracks open along the back, and the 



adult comes forth. For development a period of about five 

 weeks is required for each brood. Many cast pupa skins 

 may be found upon the older and lower leaves of the plant 

 where the larvae were first to mature. 



The adults resemble tiny white moths and are very 

 beautiful when examined under the microscope. Both 

 sexes are winged. An adult has four wings, each with a 

 single median vein. The color of the body is yellow, that 

 of the wings white. The abdomen of the female is thicker 

 and plumper than that of the male. The body, wings and 

 legs are covered with a white powdery substance, which 

 was thought to resemble flour, thus suggesting the name 

 Aleyrodes, which is from the Greek Aleurodes, meaning 

 flour-like. The antennae are six-jointed. 



Entomologically the Aleyrodidae are intermediate be- 

 tween the plant lice (Aphididae) on one hand and scale 

 insects (Coccidae) on the other, and are closely related to 

 both. In fact, for a long time entomologists classed these 

 insects with the Coccida\ 



The genus Aleyrodes has not been well studied in this 

 country, but was monographed by Signoret some twenty 

 or twenty-five years ago. 



One species infesting the Orange-tree, figured and de- 

 scribed by Riley and Howard in Insect Life, vol. v., page 2 19, 

 had been named Aleyrodes citri previously by Mr. Ashmead. 



Aleyrodes vaporariorum is mentioned by Professor L. H. 

 Bailey in Cornell Experiment Station Bulletin 28, page 58, 

 as being a pest of the Tomato-house. Professors H. Gar- 



- 





Fig. 23. — Aleyrodes vaporariorum. Westwood. 



1, Adult female. 2. Eggs. 3 Recently hatched larva. 4. Full-grown larva. 



All magnified 21 diamefers. 



man,* of Kentucky ; G. C. Davis, f of Michigan, and A. S. 

 Packard,| of Rhode Island, write of the plant-house Aley- 

 rodes under the name of A. vaporarium. A. vaporariorum 

 is the correct name, because it is the one given the insect 

 by Westwood in the original description. There is, of 

 course, a possibility that the two insects are not identical, 

 yet they are supposed to be the same species. The dis- 

 crepancy in the spelling of the specific name is doubtless 

 an oversight. 



Fumigating with tobacco will kill the adults in the green- 

 house, and this is unquestionably the best way to keep the 

 insect in check. The larvse upon the leaves may be de- 

 stroyed by applying a solution of whale-oil soap. Kerosene 

 emulsion is used with success against Aleyrodes citri upon 

 the Orange-trees in the southern states. 



The figure on this page shows the insect in the adult, 

 egg and larval stages. 



Agricultural Experiment Station, New Haven, Conn. '* ■ &• ttritlOn. 



Cultural Department. 



The Hippeastrums. — IV. 



HYBRIDS — CONTINUED 



A LARGE number of gigantic hybrids of the finest form and 

 beautiful colors have recently been introduced by Mr. E. H. 

 Krelage, of Haarlem, Holland. Just now (April iotii) the fol- 

 lowing are in flower with me : Geier Wally, rosy white ground, 



* Annual Report Kentucky Agrii ultural Experiment Station, 1S90, p. 37. 



t Insect Life, vol. vii., p. 174. 



X Guide totiic Study of Insects, oth edition, pp. 526 and 712. 



