PROC. EXT. SOC. WASH., VOL. 20, NO. 1, JAN., 1918 15 



moth 10 and of the hornet. 11 To a less extent also this is true of 

 two papers dealing with "chrysalis oil" obtained from the pupae 

 of the silkworm. 1 ' 2 



Under the head of biological chemistry may be found some 

 interesting results of experiments in feeding, some of which will 

 be referred to later. The changes caused in chlorophyll by which 

 a red pigment is produced is noted, in the case of Lepidoptera 13 

 and, in another instance, it is shown that the so called "grass- 

 hopper green" is not chloroplryll, as had formerly been supposed 

 to be the case. 14 One reference deals with the effect of starving 

 in regard to certain physiological compounds in the eggs of a 

 species' of bark beetle. 15 \Yith silk worms the effect of feeding 

 glycocoll on the properties of the silk which is produced, is 

 shown 16 and, in another investigation, the influence of lime, in 

 the food, upon the insect and its silk. 17 The latter experiment is 

 a very interesting one and the claim is made by the investigator 

 that silk worms which have had calcium salts added to their 

 food thrive upon this diet better than upon a natural one. It 

 is stated that larger pupae and cocoons are produced and a greater 

 weight of silk. 



Two investigators have occupied themselves with the problem of 

 immunity shown by certain insects to the alkaloid poison strych- 

 nine. ls 



When several workers are engaged upon the same problem it 

 sometimes happens that their results lead them to make deduc- 

 tions which are widely divergent or even contradictory. A case 

 in point concerns the question of whether the chrysalids of but- 

 terflies have the power of obtaining carbon from the carbon 

 dioxide of the surrounding atmosphere. A number of references 

 were found concerning a controversy over this question which 

 extended from 1907 to 1912. l9 One of the authors referred to 



10 Lyzzer, J. Med. Res., 16, 43-64. C. A. 1, 1293. 



11 Bertarelli and Tedeschi, Centr. Bakt. Parisitenk, 1. Abt., 68, 309-17. 

 C. A. 7, 2433. 



12 Lewkowitsch, Nahr. genussm., 12, 659-60. C. A. 1, 786. 

 Tsujimoto, J. Coll. eng. Imp. Univ. Tokyo, 4, 63-74. C. A. 2, 2024. 



13 Petersen, Naturwiss. Wochsohr., July, 1913. C. A. 7, 4019. 



14 Przibram, Ges. Physiol., 153, 385-400. C. A. 7. 

 15 Knoche, Verb. Deut. Zool. Ges., 18, 224-30. C. A. 3, 2312. 



6 Pigorini, Arch. farm, sper., 20, 225-57, 1915. C. A. 10, 74. 



17 Hatano, Bull, de 1'Assoc. sericole du Japan, March, 1916, 1-4. C. A. 

 11, 1491. 



18 Juckenack and Griibel, Z. Xahr. Genussm., 19, 571. C. A. 4, 2339. 

 J. C. de Ruijter de Wildt., Nahr Genussm., 20, 520. C. A. 5, 751. 



19 a. M. von Linden, Bonn. arch. Physiol. (Engelmann). 1907, 162, 

 208. C. A. 1, 2801. 



b. M. von Linden, Arch. anat. physiol., Suppl. Bel. 1910, 153-98. 

 C. A'. 6, 2795. 



c. E. T. v. Briicke, Arch. Nat. Phys., Waldeyer-Engolmann., Physiol. 

 Abt., 1908, 431-44. C. A. 4, 1190. 



d. Buytendijk, Biol. Zentr., 31, 643. C. A. 6. 



