370 



SCIENCE 



[N. S. Vol. XXXVII. No. 949 



different. The anatomists have a very thor- 

 ough knowledge of their subject so that they 

 may apply descriptive terms vs^ith certainty in 

 m.ost cases, and then, again, their major terms 

 are well fixed by long usage and the modifica- 

 tions proposed in the Basle system are in most 

 cases restricted to qualifying terms. Cytolo- 

 gists, on the contrary, have no such familiar- 

 ity with their subject and there is lacking an 

 agreement regarding the application of even 

 major terms. Undoubtedly the subject of hu- 

 man anatomy forms the best instance of the 

 possibility of the application of descriptive 

 terms, but even here the necessity for their use 

 is definitely denied and provided against by 

 the fourth principle which reads (Barker, 

 B. N. A.) : 



The terms shall be simply memory signs, and 

 need lay no claim to description or to speculative 

 interpretation. 



It thus appears that in two of the oldest 

 branches of biological science, general taxon- 

 omy and human anatomy, the necessity for 

 definiteness of application in terms, to the 

 neglect of descriptive value, has manifested 

 itself. It would certainly seem the part of 

 wisdom for cytologists to avoid the difficul- 

 ties which will inevitably arise through the 

 practise now prevailing in their science by 

 applying well-tried methods in their nomen- 

 clature. 



C. E. McClung 



University of Pennsylvania 



a suggested classification of writings on 

 eugenics 

 The following note is published in response 

 to various inquiries as to a schedule for 

 classifying eugenical writings, for bibliog- 

 raphies, libraries, etc. It lends itself to the 

 decimal system of classification, if desired. 



Eugenics 



0. Philosophy and bearings of; compendia, 

 essays; periodicals, societies, institutions 

 (record offices, laboratories, etc.), methods, 

 history, bibliography, biography. 



1. Racial anthropology. 



2. Genealogy or family history, eugenic 

 and cacogenic families. 



3. Heredity, including mental traits, nor- 

 mal and pathological (see " Trait, Book of the 

 Eugenics Record Office," Bulletin No. 6). 



4. Differential selection of mates and its 

 social control. 



5. DitTerential fecundity and its social con- 

 trol. 



6. Differential survival and its social con- 

 trol. 



7. Migration and its social control. 



8. Culture of the innate traits ; relations to 

 eugenics of education, religion, and work for 

 social and individual welfare. 



C. B. Davenport 

 Cold Spring Harbor, L. I., 

 February 10, 1913 



EQUINE PIROPLASMOSIS IN THE CANAL ZONE 



To THE Editor of Science : I wish to note 

 the occurrence of equine piroplasmosis in the 

 Canal Zone. The parasite closely resembles 

 Piroplasma cahalli Nuttall, 1910, and differs 

 from Nuttallia equi (Laveran) in not display- 

 ing " cross forms." 



Equine piroplasmosis has, so far as the lit- 

 erature at hand discloses, appeared in only two 

 other localities in America — Sao Paulo, 

 Brazil, and Venezuela. The infected animal 

 was an American driving horse that had been 

 on the isthmus several years and no doubt be- 

 came infected from ticks while driven out into 

 Las Sabanas to the Juan Diaz River. The 

 disease is very likely epizootic in the interior 

 of the republic, for native cattlemen speak of 

 a disease of horses there resembling anthrax. 



In view of the fact that among animals in 

 the commission corrals, it has been found that 

 horses, from their use on the trails, become in- 

 fested with ticks, Dermacentor nitens chiefly, 

 while the draft mules, from their restricted 

 use on the roads, usually are not infested with 

 ticks; it is interesting to note that piroplas- 

 mosis, a tick-transmitted disease, appeared 

 in a tick-infested horse, while murrina, the 

 trypanosomal disease of equines of Panama 

 (fly transmitted) was confined absolutely to 

 draft animals, tick-infested saddle horses 



