712 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Reflexes of Silkworm Moths.* —Vernon L. Kellogg records some 

 very interesting facts in the behaviour of the aewly hatched moths of 

 Bombyx mori. They are then sexually mature, and eager to mate The 

 males hud the females exclusively by the odour of the protruded scent- 

 glands of the female. If they find the cut-off glands, they vainly 

 endeavour to copulate with them, even when the mutilated female 

 is lying quite near. Blinded males find the females readily, but not 

 so those whose antennas have been removed. " The behaviour of males 

 with the antenna of only one side removed is striking. A male 

 with left antenna off when within three or four inches of a female (with 

 protruded scent-glands) becomes strongly excited, and moves energetically 

 around in repeated circles to the right, or rather, in a flat spiral, thus 

 getting (usually) gradually nearer and nearer the female, and finally 

 coming into contact with her, when he is immediately controlled by the 

 contact stimulus. A male with right antenna off, circles or spirals to 

 the left. . . . This behaviour is quite in accordance with Loeb's explana- 

 tion of the forward movement of bilaterally symmetrical animals." 

 Various experiments were made with moths without cephalic or thoracic 

 ganglia. Females with head and thorax cut off (and even part of the 

 abdomen) can be mated with by males, and this fractional part of the 

 female can fertilise and deposit a few eggs which begin normal develop- 

 ment. One such fragment " lived," flexible and responsible to stimulus 

 and capable of extruding the ovipositor and laying eggs, for forty hours. 

 Males without heads cannot find females, nor can they mate if placed in 

 contact with them. An experiment on equilibrium showed that the 

 equilibrating organs are not on the antennas ; they are on some other 

 part of the head. 



The author appears to regard much of the behaviour of complexly 

 organised forms, such as the moths in these experiments, as " inevitable " 

 in relatic n to physico-chemical stimuli and reactions. 



Inheritance in Silkworms.f — V. L. Kellogg publishes a first account 

 of data and results derived from a prolonged experimental study of silk- 

 worm inheritance. This study has served to test for the silkworm the 

 Mendelian principles of inheritance, as well as the actuality of the potency 

 in heredity of vigour, of sex, and of special characters, and finally, the 

 hypothesis of individual and race idiosyncrasies in matters of inheritance. 

 His conclusions are as follows : — 



Silkworms exhibit some characteristics which are alternative in 

 inheritance and which follow in their transmission exactly, or with 

 more or less approximation, Mendelian proportions. But some of these 

 characteristics are not very stable in their alternative and Mendelian 

 behaviour. Some other characteristics are not discontinuous or alterna- 

 tive in character or inheritance, but are of the nature of fluctuating 

 variations, and are strongly obedient to Galton's law of regression. 

 Larval colour-pattern differences are consistently and rigorously alterna- 

 tive and Mendelian in inheritance ; cocoon colours tend to be alternative 

 and Mendelian in behaviour, but are inconsistent as to dominancy and 



* Proc. Stanford Univ., California, 1906, pp. 152-4. 



t Leland Stanford Junior University Publications, University Series, i. (1908) 

 89 pp., 4 pis. 



