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SCIENCE 



[N. S. Vol. XXXVII. No. 951 



lumen of the uterus. So it is fed upon only 

 by the sperm itself. 



The nematodes should, therefore, be placed 

 in Faure-Fremiet's (1910) fourth class of 

 mitochondria-bearing sex-cells, in which these 

 granules produce yolk. 



Marcus, Mayer, Eomien and Faure-Fremiet 

 use the term mitochondria to describe minute 

 plastin granules found in the nucleus of the 

 spermatogonium and in both nucleus and 

 cytoplasm of the spermatocyte. They are 

 easily seen in the " perinuclear zone " of the 

 spermatid and in the " crown " of the sperma- 

 tozoon. But nowhere do these granules take 

 Benda's Krystal violet stain or transform into 

 any cell structure. Hence they have no rela- 

 tionship with true mitochondria. Meves rec- 

 ognizes their nature and origin and calls them 

 plastochondria. Van Beneden called them 

 " protoplasmic corpuscles " ; Altmann, " micro- 

 somes " ; Boveri, " archoplasm." But none of 

 these observers attributed any importance to 

 them as bearers of hereditary characters. 

 Meves (1910), however, finds (like the brothers 

 Eoja, 1891) that these granules fuse with 

 similar ones in the egg after fertilization 

 occurs, and he believes, with only this observa- 

 tion as a basis for it, that these plastochon- 

 dria are the bearers of paternal structural 

 characteristics. I have carefully studied the 

 origin and behavior of these granules through- 

 out the spermatogenesis and find that they 

 everywhere behave, like the plasmosome itself, 

 as if they were waste products of the metabolic 

 processes of the chromatin. Many of them 

 are actually thrown oS by the spermatid with 

 the cytoplasmic lobe, not only in Ascaris, but 

 in many other forms. They always take 

 plasma stains, yellow after Benda, and red 

 after Ehrlich-Bionde, both reactions char- 

 acteristic of secretions; they are pulled about 

 in the cell by the force of the centrosomes to 

 form aster rays and spindle fibers of the 

 cleavage figure; they never divide, nor grow 

 except by fusion on actual contact; in short, 

 they behave everywhere as inert formed prod- 

 ucts only. 



I believe that the observed facts of artificial 



parthenogenesis, hybridization and fertiliza- 

 tion of enucleated eggs, all argue against 

 Meves' interpretation of the role of the plas- 

 tochondria ; while these facts and the observa- 

 tions of Baltzer, Tennant and others show 

 clearly that it is the retention or elimination 

 of chromatin (or the karyochondria) that 

 determines the inheritance of paternal char- 

 acters, segregation and dominance. 



Edward E. Wildman 



TEE AMEBJCAN ASSOCIATION FOE THE 



ADVANCEMENT OF SCIENCE 

 SECTION E— GEOLOGY AND GEOGF.APEY 



The sixty -fourth meeting of Section E, Geology 

 and Geography, of the American Association for 

 the Advancement of Science, was held in the 

 geological lecture room, main building, Case 

 School of Applied Science, December 30, 1912, to 

 January 2, 1913. Vice-president James E. Todd 

 presided. The address of the retiring Vice- 

 president, Professor B. Shimek was given on the 

 subject, ' ' The Significance of the Pleistocene 

 Mollusks." Much interest was taken in the 

 papers, which are here given with abstracts: 

 Esher Terraces in Ohio: G. Feederick Wright. 

 The Wisconsin Drift-plain in the Region about 



Sioux Falls, S. D. (illustrated) : J. Ernest 



Carman. 



The region considered lies to the south of Sioux 

 Falls along the line between Lincoln and Minne- 

 haha counties, South Dakota. Professor Todd 

 and others have interpreted it as belonging to the 

 Wisconsin drift-plain, being an eastward projec- 

 tion of the James Eiver lobe to the Big Sioux 

 Valley. Professor Shimek has recently decided 

 that the. region is a Kansan drift-plain and not 

 Wisconsin. The present paper describes the char- 

 acteristics of this plain north and west of Shindlar 

 and compares it with the typical Kansan region 

 to the north and east. The evidence, chiefly 

 physiographic, indicates that the region is a Wis- 

 consin drift-plain. The conclusions of the paper 

 support, in the main, the earlier interpretation of 

 Professor Todd. 

 The Pleistocene Succession in Wisconsin: Samuel 



WEmMAN. 



A brief statement is given concerning present 

 knowledge of the drift and associated surface 

 deposits in Wisconsin, with a map showing dis- 

 tribution of the formations. There appear to be 



