April 7, 19]] J 



SCIENCE 



551 



hanna rivers, but long after the uplift of the 

 Cretaceous peneplain the Schoharie captured this 



In the southern and western Catsliills the streams 

 are stOl worliing in massive roelis, developing the 

 plateau type of topography. 



The Iron Ores of Sweden: Waldemak Lindgeen. 

 Mr. Lindgren discussed nature and origin of 

 the principal iron ore deposits and exhibited nu- 

 merous specimens. 



Edson S. Bastin, 



Secretary 



THE BOTANICAL SOCIETY OP WASHINGTON 



The 71st regular meeting was held at the Cos- 

 mos Club, Tuesday, March 7, 1911, at 8:00 p.m. 

 President W. J. Spillman presided. Thirty-two 

 members were present. Mr. H. C. Slieels was 

 elected to membership. 



Mr. W. A. Orton discussed current dictionary 

 definitions of the term ' ' genetics ' ' and showed 

 that the usage attributed to Ward in the new 

 Century is faulty, as that author proposed the 

 term as an antithesis of ' ' telics ' ' and did not 

 extend it to other phenomena of evolution. The 

 usage in the new Webster was held to be faulty in 

 that it does not convey the new view point of 

 scientific experimentation. The term was thus 

 newly defined : ' ' Genetics — the application of sci- 

 entific methods to the study of evolutionary prob- 

 lems; the investigation, in an exact manner and 

 by experimental means, of the facts pertaining to 

 heredity, variation and allied subjects." 



The following papers were read: 



Studies of the Life History of the Head Smut of 



Sorghum: Alden A. Pottek. 



Attempts at preventing this smut by seed treat- 

 ments have failed. Numerous inoculation experi- 

 ments have been performed, but neither local in- 

 fection, as in corn smut, seedling infection, as in 

 the kernel smuts, nor floral infection, as in the 

 loose smuts of barley and wheat, has been demon- 

 strated. No theory of local infection can be enter- 

 tained, however, since detailed histological study 

 has shown that the host plant is affected as a 

 whole. Since the infection is general, then, it 

 must talse place at an early stage. 



Peculiar floral alterations were shown to be 

 caused by the smut and to contain the smut 

 mycelium, and it was suggested that some grains 

 may develop with the fungus in them and the 

 smut, therefore, be hereditary as is the fungus in 

 certain Lolium species. 



Dimorphic Leaves of Cotton, and Allied Plants: 



O. P. Cook. 



This paper reported the existence of a definite 

 dimorphism of leaves in an Egyptian variety of 

 Hibiscus cannaiinus. The basal leaves are simple, 

 but there is an abrupt transition to deeply lobed 

 leaves near the middle of the stalk. A second 

 Egyptian variety has all the leaves simple. Par- 

 allel variations of leaf -forms exist in cotton, okfa 

 and Ingenhousia, a wUd relative of American up- 

 land cotton, found in Arizona and Mexico. The 

 so-called okra varieties of upland cotton, with 

 narrow-lobed leaves, correspond to the dimorphic 

 Egyptian variety of Hibiscus cannabinus. Hy- 

 brids between okra cottons and broad-leaved varie- 

 ties have shown intermediate forms of leaves in 

 the conjugate generation and Mendelian segrega- 

 tion in the perjugate generation. Dimorphism and 

 Mendelism were treated as analogous forms of 

 alternative expression of characters, the current 

 theory of alternative transmission being consid- 

 ered unnecessary. 



Plant Eemains Composing Coals : Dr. E. Thiessen. 



A brief review of the literature on the micro- 

 scopic investigations of coals was given, in which 

 the views of Bertrand and Eenault and Potonie 

 were dwelt upon. 



Since every interpretation of any investigation 

 must agree with every known scientific fact, in the 

 present investigation on coal the structure, organ- 

 ization, morphology and chemistry of the living as 

 well as of fossil plant forms had to be considered. 

 Plant components of coals may be divided into 

 two classes: those less resistant to chemical agen- 

 cies, and those less easily or very difficultly at- 

 tacked by such agencies. Among the latter class 

 may be recounted the lignocelluloses, the true 

 celluloses, the cuto-celluloses, especially the leaf 

 cuticles, spore- and pollen-exines, the resins and 

 the waxes. It has been found that the coals are 

 composed in a large proportion, if not entirely, 

 of this class. 



The lignites are composed approximately of 

 from 75 to 85 per cent, of stems, branches and 

 twigs, almost entirely of coniferous origin, in a 

 very much vertically compressed and changed con- 

 dition, the interstices being filled in with a plant 

 refuse, analogous to a recent black peat, in which 

 resins, pollen-exines, spore-exines, cuticles and 

 waxes form an important part. These constituting 

 a crystalloid component are imbedded in a colloidal 

 substance, mainly a derivative of cellulose. Here 

 as in all the coals, nothing but the outer wall or 



