750 



NATURE 



[June lo, 1922 



A Supposed Ancestral Man in North America.^ 

 By Dr. A. Smith Woodward, F.R.S. 



PROF, H. F. OSBORN has just described a water- 

 worn small molar tooth from a Pliocene forma- 

 tion in Nebraska, U.S.A., as the first evidence of an 

 anthropoid primate discovered in the New World. 

 The specimen was found in the Snake Creek beds by 

 Mr. Harold J. Cook, who has already made known 

 numerous important remains of Pliocene mammals 

 from Nebraska, some showing marked Asiatic affinities. 

 With the aid of Drs. W. D. Matthew, W. K. Gregory, 

 and M. Hellman, Prof. Osborn has determined the 

 tooth to be a second upper molar, and he has named 

 the unknown genus and species to which it belonged 

 Hesperopithecus haroldcookii. It is nearly as large as 

 the second upper molar of an American Indian, and 

 its two diameters are almost equal. The kind of wear 

 shown by its evenly concave coronal surface " has 

 never been seen in an anthropoid tooth." In type 

 the tooth is " very distant " from the corresponding 

 tooth of the gorilla, gibbon, and orang ; it is " still 

 very remote " from that of a chimpanzee. It is also 

 " excluded from close affinity to the fossil Asiatic 

 anthropoid apes " represented by teeth found in 

 India; and " it cannot be said to resemble any known 

 type of human molar very closely." Indeed, " it is 

 a new and independent type of Primate, and we must 

 seek more material before we can determine its re- 

 lationships." 



The statements quoted make it diflficult for one 

 who has not seen the tooth to understand why Prof. 

 Osborn even refers it to a Primate ; and the published 

 figures are not very helpful. The crown may be 

 described as nearly triangular in shape, with bluntly 

 rounded angles, a slightly raised and partially crimped 

 rim surrounding a gently concave surface. The root 



' H. F. Osborn, " Hesperopithecus, the first Anthropoid Primate found 

 in America," American Museum Novitates, No. 37 (reprinted, without 

 figures, in Science, vol. 55, pp. 463-465, May 5, 1922). 



is very massive, and at a considerable distance below 

 the crown it becomes bifid, the smaller portion extended 

 beneath one margin of the crown, the larger portion 

 beneath and inclined towards the opposite apex. On 

 one side of the root, between the bifurcation and the 

 crown, there is an irregular indentation, from which 

 Prof. Osborn supposes a third root-fang has been 

 broken away. No stump of this third fang, however, 

 is shown in the drawing. 



In determining the tooth to be an upper molar. 

 Prof. Osborn regards the edge with the smaller portion 

 of root as external, and the tapering opposite end 

 with the larger portion of root as internal. The 

 hypothetically restored piece of root thus becomes 

 posterior. It is, however, equally reasonable to in- 

 terpret the so-called external border as anterior and 

 the tapering end as posterior. If, then, the indented 

 lateral portion of the root never bore another fang, 

 the tooth becomes a lower molar. If this interpreta- 

 tion be admitted, comparison should be made not 

 with any Primate tooth, but with the last lower molar 

 in the primitive bears. In general appearance and 

 shape the crown is very suggestive of that of the last 

 molar in the lower jaw of some species ascribed to 

 Hysenarctos and related genera ; and as primitive 

 bears of this group are already known by several 

 fragments from the Pliocene of North America, material 

 will eventually be available for comparison. The 

 root of the last lower molar of Hyaenarctos unfortun- 

 ately appears to be unknown ; but in the modern 

 Ursus, in which the tooth in question is extremely 

 variable, the root is often bifid, as in the new fossil 

 from Nebraska, while between the bifurcation and 

 the crown there is a hollowing of its outer face. There 

 is, indeed, some reason to suspect that Hesperopithecus 

 has received an inappropriate name. 



Synthetic Dyes as Antiseptics and Chemotherapeutic Agents. 



By Prof. C. H. Browning, University of Glasgow. 



GENERAL interest in this subject has been recently 

 stimulated by accounts in the daily press of a 

 communication to the Society of Chemical Industry at 

 Manchester by Messrs. Fairbrother and Renshaw.^ 

 The fact, however, ought not to be overlooked that 

 much work has been in the past devoted to these 

 problems by a number of investigators. That certain 

 dyes of the triphenylmethane class possess marked 

 antiseptic properties has long been known. Thus 

 Stilling 2 in 1890 noted the powerful effect of ethyl 

 violet on staphylococci (one of the commonest group of 

 organisms which cause suppuration). He suggested 

 the use of a mixture of allied dyes in the treatment 

 of infective conditions, especially of the eye. But 

 Stilling's suggestion found little favour with practical 

 surgeons. As compared with phenol or mercuric 

 chloride, the antiseptic dye-stuffs in general exert 

 their lethal action on bacteria relatively slowly ; thus, 

 when tested by the usual method, in which only a brief 

 period of contact between the organisms and the 



NO. 2745, VOL. 109] 



chemical agent is permitted, these dyes appear to act 

 very weakly. It is probably for this reason that they 

 were neglected. 



The fact was overlooked that from the beginning 

 of contact very high dilutions of antiseptic dyes may 

 inhibit bacterial activity and that such " bacterio- 

 static " action can be utilised advantageously for thera- 

 peutic purposes. Churchman,^ however, in America 

 has investigated more recently the allied product, 

 gentian violet, and has emphasised its value in the 

 treatment of certain local pyogenic infections. The 

 diaminotriphenylmethane dyes, malachite green and 

 brilliant green, were shown to be actively antiseptic by 

 Drigalski and Conradi^ in 1902, and brilliant green has 

 been applied with success in the treatment of infected 

 wounds. 



Investigations carried out with the view of compar- 

 ing the antiseptic properties of various classes of dyes 

 by Browning and Gilmour^ confirmed the fact that 

 a considerable number of basic compounds showed 



