March 21, 1913] 



SCIENCE 



455 



ing an enzyme and therefore such a thing as 

 a pure enzyme is now unknown. For this rea- 

 son the chemical analyses of dried " enzyme 

 preparations " signify little, because it is im- 

 possible to know what portion of the prepara- 

 tion is enzyme and what is impurity. Pend- 

 ing the discovery of some method for crystal- 

 lizing enzymes this branch of their study is 

 practically at a standstill. On the other hand, 

 the study of the mode of action of enzymes 

 and the influence of temperature, acids, etc., 

 upon their catalyzing power is advancing 

 rapidly and it is with this subject that Pro- 

 fessor Euler's treatise deals. To quote from 

 the preface, he " has attempted to review the 

 more important facts of enzymology from a 

 general standpoint and to fit them, as far as is 

 possible, into their proper places in the fabric 

 of general and physical chemistry." This 

 hook is the first in which an attempt has been 

 made to describe this branch of science from 

 the standpoint of theoretical chemistry and 

 special credit is due Professor Euler for his 

 excellent treatment of the subject. The fol- 

 lowing chapter titles may serve to give an idea 

 of the contents of the book : Special chemistry 

 of the enzymes, their physical properties, their 

 activators and poisons, the chemical dynam- 

 ics of enzyme reactions, the influence of tem- 

 perature and radiation on enzymic reactions, 

 the chemical statics of enzyme reactions, 

 enzymic syntheses and the specificity of 

 enzyme action. The work of translation by 

 Mr. Pope has been very carefully done. The 

 publishers are also to be commended for the 

 quality of the printing and binding. 



C. S. Hudson" 



SPECIAL AETICLES 

 MITOCHONDRIA IN ASCARIS SEX-OELLS 



During the course of preparation of a 

 thesis for the Doctor's degree at the Univer- 

 sity of Pennsylvania, entitled " The Sperma- 

 togenesis of Ascaris megalocepliala with special 

 reference to the two Cytoplasmic Inclusions, 

 the Refractive Body and the 'Mitochondria'; 

 their Origin, Nature and Role in Fertiliza- 

 tion," the following observations were made: 



The refractive body arises, as Marcus 



(1906), Mayer (1908) and Eomieu (1911) 

 point out, by the fusion of the refringent 

 vesicles while still in the vas — probably just 

 before copulation occurs. The refringent 

 vesicles arise from minute granules scattered 

 here and there throughout the cytoplasm in 

 the early growth period of the spermatocyte. 

 These granules stain blue after the material is 

 fixed in Benda's modification of Flemming's 

 strong solution and stained in Benda's 

 " Krystal Violet." This reaction is char- 

 acteristic of true mitochondria. Granules 

 staining exactly like these are found constantly 

 in the nucleus of the spermatogonium, and 

 these actually pass through the nuclear mem- 

 hrane into the cytoplasm of the sperma- 

 tocyte. This blue staining material, or 

 true mitochondria, is apparently derived di- 

 rectly from the chromatin because in several 

 cases chromosomes in the spermatogonia! 

 nuclei were cut, showing the red-brown inter- 

 ior (the typical reaction to Benda's stain for 

 chromatin) covered by a blue layer. Thus the 

 refractive body is ultimately derived from the 

 chromatin of the spermatogonium, and it is 

 formed by true mitochondria; these are not 

 only nuclear in origin, they are derivatives of 

 the karyosome. They should, therefore, be 

 called karyochondria to distinguish them 

 clearly from the plastochondria (Meves) which 

 are derived from the plasmosome of the 

 spermatogonial nucleus. 



The refractive body has but one function — 

 namely, to feed the spermatozoon on its long 

 and exhausting journey (by pseudopodial 

 creeping) to the " entrance region " at the 

 proximal end of the uterus. This is proven by 

 the fact that many eggs are entered there by 

 spermatozoa which have lost every trace of the 

 refractive body; and further, by the fact that 

 the decrease in size of this body takes place 

 equally from all sides, showing that it is the 

 surrounding layer of cytoplasm, and not the 

 uterine epithelial cells, as all other authors 

 maintain, which is the agent of its absorption. 

 Not only is its axial symmetry maintained 

 during the stages of degeneration while 

 crowded between the epithelial cells, but also 

 when lying amongst eggs far out in the 



