650 



SCIENCE 



[N. S. Vol. XXX. No. 775 



Bolin would do away with, the word instinct ; 

 and finalism is for him an explanation that 

 comes into play only after a first appeal to 

 other more mechanical inherent causes. " For 

 Jennings," he says, " selection would be ef- 

 fected among the various movements of trial, 

 and the final result would be a tropism. For 

 us, the tropism, as Loeb has said, is some- 

 thing inherent, and it would be one of the ele- 

 ments on which selection would be exercised." 

 Thus for Bohn the psychic evolution of ani- 

 mals would result, in some sort, from the 

 struggle which occurs among the old survivals 

 of the past (as tropisms and the phenomena of 

 differential sensibility), and the new acquisi- 

 tions (fruit of associative memory). This is 

 made only painfully, and to a certain degree, 

 by " coups de revolutions." 



Finally Bohn believes that we are suffi- 

 ciently advanced in our study of animal be- 

 havior to be able to enunciate certain laws, 

 not only for the tropisms and differential 

 sensibility — " a conception which for the first 

 time appears in a book of animal behavior " 

 — but also for the associative phenomena. He 

 holds that animal psychology is now no more 

 open to the criticism that its " explanations," 

 such as tropisms, differential sensibility, as- 

 sociations of sensations, etc., are simply 

 labels and terminology and do not really ex- 

 plain the animal mechanism in its behavior, 

 than the other sciences whose more familiar 

 terminology, as " gravitation," " atoms," etc., 

 seem, but in reality only seem, to be so truly 

 explanations. 



When Newton discovered the laws of universal 

 gravitation, he had to confess that he had no 

 idea as to the cause of this phenomenon. Is his 

 merit less great for that? Have not his ideas, 

 although incomplete, permitted us to build a 

 great scientific structure that compels all our 

 admiration, although we may be to-day quite as 

 little advanced as to the subject of the nature of 

 gravitation as was Newton in 1687 or Epicurus 

 three hundred years before Christ? Now in the 

 domain of zoological psychology, the scholars of 

 the new school inaugurated by Jacques Loeb seek 

 to imitate Newton in the domain of astronomy; 

 they analyze the phenomena and establish their 

 laws. ... As said recently by my regretted master 

 Oriard : " The analysis which is necessary to let us 



master the phenomena of life furnishes us a surer 

 base than that which tends directly to explain 

 thes-e phenomena." 



Veenon L. Kellogg 

 Pabis, 

 April 



NOTES ON ENTOMOLOGY 

 The report' of M. Eoubaud, who spent a 

 year and a half in the Congo region as a mem- 

 ber of a commission to study sleeping sickness, 

 is before us. It goes, in much detail, into the 

 habits and habitats of Glossina palpalis, the 

 particular species of tsetse files which is con- 

 cerned in the spread of this dread disease. 

 Agreeable to the general rule he finds that the 

 flies are very local, rarely going more than 300 

 yards, but may be carried by air currents and 

 storms to greater distances. They bite only 

 during the daytime, and feed on a great 

 variety of animals. There is a long account of 

 the larva, and of its curious posterior lobes, 

 which apparently represent the posterior 

 spiracles. The fly deposits the full-grown larva 

 on the ground, which crawls into the soil and 

 there pupates. The author details a number 

 of experiments on the efi^ects of different tem- 

 peratures on the pupsB. Species of Bembex, a 

 spider (Dolomedes), a beetle (Cicindela) and 

 ants are among the natural enemies of the 

 Glossina. 



A large part of the work is taken up with 

 a study of the Trypanosomes, and five of the 

 plates illustrate them. A long bibliography is 

 appended to the article. 



The new parts of Wytsman's " Genera In- 

 sectorum " are as follows : Fasicle 76 is by J. 

 J. Kieffer on the small Hymenoptera of the 

 family BethylidEe; 30 pp., 3 pis. He con- 

 siders that they are most closely related to 

 the Scoliidse. Fasc. 7Y, by the same author, 

 treats of the small family Stephanidae; 10 pp., 

 1 pi. He adopts the classification of Ender- 



^ " La Glossina palpalis ; sa biologie, son role 

 dans I'gtiologie des Trypanosomiases," Rapport 

 Mission d'^tudes de la Maladie du sommeil au 

 Congo Frangais (1906-1908), pp. 383-652, 8 pis., 

 4to, 1909, Paris, by E. Roubaud. 



