Biology Pamphlets (Volume 1708) (Paperback)

This historic book may have numerous typos, missing text, images, or index. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. 1915. Not illustrated. Excerpt: ... OBSERVATIONS ON THE LIFE HISTORY AiD HABITS OF PITYOGENES HOPKliXSI SWAINE M, W. Blackman, Ph. D. (With Six Plates) The study of the life history and habits of the various members of the superfamily Scolytoidea offers as many points of interest either from the standpoint of pure science or from the economic aspect as does that of any other group of beetles. In spite of this, however, careful study of the biologies of this very interesting group of insects has been neglected in this country except in the case of a very few forms which are of great economic importance. Perhaps explanation of this neglect is to be found in the difficulties experienced in studying these insects consequent upon their very secluded life, as they remain either under the bark or within the wood of the host plant throughout their life, except for the short time required in finding a new host. However, by the exercise of a little ingenuity and of considerable patience, the main facts of their life histories and many of their interesting habits can be observed. This is especially true of those members of the group which habitually feed and breed in the thinner barked portions of cut trees, as the habits of these render them more easy of manipulation in the insectary and more amenable to observation in the laboratory. Most of the observations here recorded were made upon insects in artificial cultures in the laboratory, supplemented wherever possible by observations in nature. In the laboratory the conditions of moisture, etc., were kept as near as practicable to conditions which prevailed in the field and observations upon the length 'of the various stages of the life history have been checked up by similar data collected in the field. Detailed study of the habits of the insect in...