varying degrees of liquid content until the 

 preferred consistency is determined. 



Preventing Escape of Living Insects. A 

 line of vaseline or glycerine spread thin 

 with the finger around the top of a con- 

 tainer will prove an effective barrier to 

 insects as they are unable to crawl over it. 



This keeps forms from escaping when col- 

 lecting material or when adding food to 

 the culture. At other times a layer of 

 cheesecloth or other cover, held firmly in 

 place over the cage, keeps the specimens 

 in and allows ventilation and evaporation 

 of moisture. 



BOOKS FOR ENTOMOLOGISTS 



C 601 A Glossary of Entomology; J. R. de la Tor- 

 re Bueno. This is a completely revised edition 

 of Smith's "Explanation of Terms." The new 

 edition of this classic work contains more than 

 12,00 definitions, as well as sections on biological 

 chemistry, ecology and medical entomology. Ap- 

 pendix of abbreviations and signs. Eight newly- 

 drawn plates of structures 5.00 



C 607 Culture Methods tor Invertebrate Animals. 



A compendium prepared co-operatively by Am- 

 erican zoologists under the direction of a com- 

 mittee from Section F of the American Associa- 

 tion for the Advancement of Science 4.00 



C 609 A Manual of Entomological Equipment 

 and Methods, Part I; Peterson, Alvah. Exhaus- 

 tive, illustrative treatment of equipment for 

 handling insects, especially living ones 3.75 



C 610 Same, Part II. Information on how to 

 rear and handle living insects, and containing 

 much information on collecting, shipping liv- 

 ing insects and collections, and insect photog- 

 raphy 4.50 



C 625 Field Book of Insects; Lutz, F. E. Third 

 edition. Indispensable pocket companion for 

 field and library. About 800 illustrations, many 

 in color- 3.50 



C 627 The Insect Book; Howard, Leland O. A 

 popular account of the bees, wasps, ants, grass- 

 hoppers. Hies and other North American insects 

 exclusive of the butterflies, moths and beetles, 

 with full life histories, tables and bibliog- 

 raphies 5.00 



C 629 An Introduction to Entomology; Corn- 

 stock, J. H . 9th edition, revised. More advanced 

 and compiehensive than the preceding. The 

 best known American book on general Entomol- 

 ogy. Now in press. Write for prices. 



C 630 Fundamentals of Insect Life; Metcalf, C. 

 L. and W. 1'. Flint. A text for general use with 

 a biological emphasis. Somewhat briefer treat- 

 ment than in C 6G4 by the same authors 4.00 



C 639 Meadow and Pasture Insects; Osborn. 

 Here is a unique and fresh approach to the 

 large group of insect pests on the farm. The 

 ecological aspects are treated as well as the sys- 

 tematic and much original material is presented. 

 The book is replete with illustrations, bibliog- 

 raphy and index 3.75 



C 647 A Lalnnatory Guide in Entomology for 

 Introductory Courses; Mathcson, Robert. An ex- 

 cellent guide intended for use in elementary 

 courses in entomology. It includes drawings the 

 student is supposed to study and label, others 



of life histories, morphology and variations in 

 insects. There are keys to the important fam- 

 ilies of the main orders annd an exercise on 

 wing venation to assist in learning taxonomic 

 characters of some groups 2.00 



C 664 Destructive and Useful Insects; Metcalf, C. 

 L. and W. P. Flint, 2nd edition. Exhaustive 

 text for general use or for economic entomology. 

 Relation of insects to agriculture, domestic ani- 

 mals, disease, industry 7.50 



C 670 Orthoptera of Northeastern America; 

 Blatchley, W. S. The best known work on this 

 Order. Cloth 6.00 



C 676 Handbook of the Odonata of North Amer- 

 ica; Needham, J. G. Authoritative treatment by 

 the outstanding , expert 7.00 



C 677 Plecoptera of North America; Needham, 

 J. G. and V. \V. Claassen. Full discussion of the 

 group by noted authors 5.00 



C 680 Heleroptera or True Bugs of Eastern 

 North America; Blatchley, W. S. Monograph of 

 the group by a recognized authority. Cloth 10.00 



C 688 A Key to the North American Families of 

 Beetles. Reprinted from the foregoing Manual. 

 Useful for collectors and for classes in Entomol- 

 ogy .35 



C 700 The Butterfly Guide; Holland, W. J. Pock- 

 et field manual with brief descriptions and color 

 plates. Flexible cloth 1.25 



C 703 How to Know the Butterflies; Comstock, 

 J. H. and A. B. Comstock. Fine elementary 

 work for identification 3.50 



C 706 The Butterfly Book; Holland, W. J. New, 

 enlarged edition of this standard reference 

 work 10.00 



C 707 The Moth Book; Holland, \V. J. Com- 

 panion volume to the preceding and equally as 

 well known. Best available single volume on 

 moths __ 5.00 



C 725 The Families and Genera of North Amer- 

 ican Diptera; Curran. C. H. The outstanding 

 recent work on the group 7.50 



C 726 Handbook of the Mosquitos of North 

 America; Matheson. Robert. Excellent treatise 

 on this important group 5.50 



C 736 Bees and Wasps; Falter. O. H. Cambridge 

 Manual 1.00 



C 740 Ants, Their Structure, Development and 

 Behaviour; Wheeler, W. M. A biological clas- 

 sic 7.50 



