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of the 3 T ouDg locusts. This plan is believed to be feasible, as the breeding grounds are 

 not co-extensive with the so-called Permanent region, but are limited to the richer 

 valleys, plateaus and river borders within it. 



The Commission will also, it is understood, in its forthcoming report, recommend 

 to the Government a scheme for a system of warning and prevention, through the aid 

 of the mounted police patrol of the Dominion Government, and our signal bureau and 

 military posts. 



Having been favoured with a transcript of the subjects to be treated of in the 

 forthcoming Second Report of the Commission, and the assignment of subjects to the 

 respective members of the Commission, I have no hesitancy in giving assurance of a 

 volume of unusual interest and value. It is to be hoped that Congress will not repeat 

 the inexcusable blunder of ordering of it an edition by far too small to supply the 

 demand, or for the accomplishment of a main object in its labourious preparation — the 

 diffusion of the needed information among those to whom it could not fail of proving 

 beneficial. 



The Commission is also occupied with investigation of the Hessian-fly and the 

 Chinch- bug — each of which are chargeable with annual injuries to the amount of 

 several millions of dollars. 



The investigation of the natural history and habits of the Cotton-worm, com- 

 menced by the Department of Agriculture last year, has by direction of Congress, been 

 transferred to the Entomological Commission. Prof. Riley has been pursuing its study 

 in Southern Texas and in the Gulf States, aided by special assistants, and it is believed 

 that discoveries have recently been made which will reduce the cost of destroying the 

 larvae to perhaps a fourth of what it has hitherto been. 



Among the special subjects of study which have claimed attention lately, an inter- 

 esting one has been the pupation of butterflies. Observations made during the past year 

 on the pupation of some of our butterflies have shown us that we have been at fault in 

 accepting the account given of it by Reaumur over a century ago, and received and quoted 

 by subsequent authors. The most interesting operation iu the pupation of the suspensi 

 butterflies is the withdrawal of the chrysalis from the larval skin, the casting off of the 

 skin with its attachment by the terminal legs to a button of silk spun for the purpose by 

 the larva, and the attachment and suspension of the chrysalis by its anal spine to the silk 

 button. Reaumur represented it as accomplished by the chrysalis in its extensions and 

 contractions grasping the larval skin between the segments, and by this means raising 

 itself until it regained the button. Recently Mr. Osborne, an English Entomologist, 

 discovered a membrane serving as a suspensory agent in the change to the pupal state, 

 and for the first, questioned the account given by Reaumur. His observations were con- 

 firmed by those of Mr. W. H. Edwards, and followed up by additional observations on 

 large numbers of Nymphalidae and Danaidse, some of which have been presented in the 

 . Canadian Entomologist. There seems to be no question of the existence of such a mem- 

 brane, and that it consists of the portion of the larval skin lining the region of the rec- 

 tum, caught upon two knobs conveniently placed for the purpose. Prof. Riley, in a 

 communication to Psyche (vol. ii., p. 249) finds other means of chrysalis suspension — the 

 principal one being the shed intestinal canal, and accessory ones, the tracheal vessels of 

 the last pair of spiracles ; these Prof. Riley regards as the principal agents in suspension. 

 In opposition to this, Mr. Edwards considers these ligaments as of but little, if any, ser- 

 vice, and finds the membrane to furnish all the requisite support. Additional observa- 

 tions are required to reconcile these different \iews. 



The beds of fossil iusects recently discovered in the Tertiaries of our western Terri- 

 tories are proving to be wonderfully rich in number of species and condition of preserva- 

 tion. From a single small basin exposed by a railway cut in the vicinity ol Green River 

 Station, Union Pacific Railroad, in Wyoming, Mr. S. H. Scudder in Fossil Insects of the 

 Green Ricer Shales (Ball. U. S. Geolog.-Geograp. Surv. Terr., iv., No. 4, pp. 747-776) 

 enumerates eighty species, representing all the orders of the Insecta except L^pi loptera. 

 An idea of the richness of these beds maybe obtained from the statement, that a two 

 hours' search was rewarded by the collection of fifty new species. We are glad to learn 

 that Mr. Siudder is engaged upon a general work on our fossil insects, which will form 

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