ENTOMOLOGY. 765 



groups. An extended bibliography on entoniology is given, reprinted from Bulletin 

 24 of the Division of Entomology of this Department, and short chapters are pre- 

 sented on methods of collecting and preserving insects for study. The plates are 

 reproduced from photographs and are all original in this volume. 



Injurious insects, E. Fleitiavx {A(/r. Prat. Pays Chaiuh, 1 {1901), No. 3, pp. 

 393-396). — Brief notes are given on a species of Arjeocerus which attacks menado 

 coffee when stored, eating out the inside of the berries. A brief account is also given 

 of Dryoca?tes, injuring the custard apple; Apate monacha, an enemy of coffee and 

 cacao, and Prodenia littoralis, which attacks the cotton plant. 



The potato worm in California (Galechia operculella), W. T. Clarke {Cal- 

 ifornia Sfa. Ihil. 135, pp. 30, figs. 10). — This is considered the most important insect 

 pest of the potato in California, the damage to the potato crop being estimated in 

 some years at 25 per cent. Following upon the attacks of this insect various fungi 

 are observed to obtain a foothold in the injured portions of the potato and hasten 

 the destruction of the tubers. Injuries to potatoes in the field are usually not so 

 great as in storage, though sometimes the whole crop is destroyed. Bibliographical 

 notes are given in connection with the various descriptions and published articles of 

 this insect. The species is described in detail in all its stages. The eggs are laid 

 either upon a stem of the potato vine or in the bodies of the tubers. Usually the eggs 

 are deposited singly, but sometimes more are laid near the same potato bud. The 

 color of the larva depends somewhat upon the material upon which it is feeding, 

 whether the inside of the tuber or the green material of the stem or surface of the tuber. 

 The larva when 6 weeks old comes to the surface of the tuber and pupates in 

 the mouth of the burrow, or in some depression of the potato, or in the cracks of the 

 bins or sacks in which the jiotatoes are stored. The life history of this species was 

 carefully followed by the author, and the complete life cycle is stated as being ordi- 

 narily from 63 to 69 days, except for the winter generation, when 84 or 85 days may 

 be required. The egg stage requires from 7 to 10 days, the larval from 42 to 45 days, 

 and the pupal from 14 to 16 days. The injur}^ from this insect may be to the grow- 

 ing plant and to the tubers. When the growing plants are attacked the eggs are 

 deposited at the base of the leaf and the larv;e, on hatching, bore downward through 

 the stem and finally enter the tuber. In the tuber they feed either through the 

 substance or immediately underneath the epidermis. Potatoes may therefore 

 become infested through the stalk, through tubers which are exposed in the hill, 

 through tubers which are allowed to lie on the ground for some time after digging, 

 and while in storage. Field experiments demonstrated that if affected stalko are 

 removed and destroyed as soon as thej' are noticed, the infestation does not proceed 

 any further. It was found, also, that lantern traps were very effective in catching 

 the moths. More moths of this species than of all other species combined were cap- 

 tured by lantern trajis, and 60 per cent of those captured were females. The larva 

 feeds inside of the stem or tuber, and therefore no spraying experiments were tried. 

 It was demonstrated by experiments that when the earth was well pulverized about 

 the hills and all potatoes carefully covered, no infestation took place, although 

 check hills which were covered with cloddy or lumpy .soil became quite badly 

 infested. It was therefore concluded that careful, compact hilling reduces the infes- 

 tation to a minimum. Experiments showed that when potatoes were exposed after 

 digging, especially in the evening or over night, a (;onsiderable proportion of the 

 tubers almost invariably l)ecan)e infested. When potatoes which were known to lie 

 uninfested were piled up in the field and covered with infested stalks, it was found 

 that about 70 per cent l)ecame infested, while potatoes which were not covered with 

 stalks remained uninfested. A series of exi»eriments were conducted for the purpose 

 of determining the effectiveness of removing and destroying the stalks while the 

 larvie were still in them. It was found that by destroying all of the potato tops about 

 one week before the time of digging and while the larvse were still in the stalks that 



