2714 Journal of Applied Microscopy 



collides with a female the latter becomes quiet at once and the male grasps her. 

 If two females collide both immediately become quiet, but as as neither is clasped 

 they soon start swimming again. Finally if two males collide each tries to seize 

 and clasp the other, and, of course, on account of their struggles neither is suc- 

 cessful. It was shown experimentally by cutting off the large second gnatho- 

 pods (the principal means of defense) from males and then putting these muti- 

 lated specimens into a dish with normal males, that such mutilated and defenceless 

 males were carried about by the others exactly as if they had been females. So 

 it appears that practically the sole method by which sex recognition is secured 

 among the Gammaridea depends on the reactions of individuals when they come 

 into contact with other individuals of the same species. r. p. 



Axenfeld, D. Invertin in Honig und im Insek- Starting from the fact that in the resi- 

 tendarm. Zentralbl. f. Physiol. 17: 268 and due remaining after dialyzing honey 

 " ^' ^ ■^' invertin is present, Axenfeld has found 



a ferment capable of inverting cane sugar in the intestine of a number of species 

 of insects. Such a ferment is present in the intestine of the wasp, Musca car- 

 naria, many Lepidoptera, including Pieris, Vanessa, and the caterpillar of Car- 

 porapsa pom. Among the Coleoptera it was found in Carabus, Dyticus, Melo- 

 lontha, Notonectes and Hydrophilus. It was also found in Cicada com. 



R. p. 



Folin, 0. On Rigor Mortis. Amer. Jour. The object of this work is to prove 

 ysio . . 374-j79. ^9°j- |.j^^j. ^^^ prevailing view as to the cause 



of a muscle going into a state of rigor mortis is incorrect. It is generally held 

 that rigor mortis is due to the coagulation of some substance in the muscle 

 plasma. Folin shows that this view is untenable, by producing rigor mortis in 

 frog and fish muscle by lowering the temperature to - 15° C. There is absolutely 

 no evidence that any coagulation takes place under the circumstances. Yet the 

 rigor mortis produced is typical. R. p. 



Kobert, R. Ueber einige Enzyme wirbellosen I" ^his paper the author SUms up the 

 Thiere. Arcii. f. d. ges. Physiol. 99: 116- results of his own and his Students' 

 ' ^ •^' work on enzymes present in inverte- 



brate organisms. He was able to obtain enzymes in different organs of a variety 

 of invertebrates, including representatives of practically all of the larger groups 

 beginning with the coelenterates. Nearly all the common sorts of enzymes were 

 found. The paper forms an excellent reference work on the subject. r. p. 



