Tecembeb is, 190S] 



SCIENCE 



885 



an informal way for the purpose of collecting 

 suggestions and information. If the move- 

 ment seems to he of interest to those who are 

 reached hy this letter, a more formal organ- 

 ization can be perfected later and the con- 

 gratulatory message can be issued by a repre- 

 sentative committee. 



The undersigned, acting as secretary for the 

 preliminary informal coromittee, begs leave to 

 request (1) suggestions with regard to the 

 mode of procedure which would be most effect- 

 ive in presenting to Leipzig University the 

 expression of congratulation from former 

 American students; (2) information with re- 

 gard to Americans in all departments who have 

 received their degrees at Leipzig. The present 

 list is complete for all names included in 

 "American Men of Science"; it is otherwise 

 very fragmentary and should he supplemented 

 even at the risk of duplicating names from' 

 various sources. 



It is requested that replies be sent at the 

 earliest possible moment in order that the 

 organization may be completed before Jan- 

 uary. 



For the Committee, 



Charles H. Judd 



Yale Univeesity, 

 New Haven, Conn., 

 December 2, 1908 



MALARU IN THE WEST INDIES 



To THE Editor of Science: In Science for 

 August 28, 1908, p. 273, a note taken from the 

 London Times appears in which it is stated 

 that " Malaria is very much less common in 

 Barbados than in other West Indian islands " 

 and that the small fish known as " millions " 

 (Girardinus poeciloides) " destroys large num- 

 bers of the larvae of mosquitos that spread 

 malaria." 



These are the usual newspaper statements 

 regarding the habits of these very interesting 

 little fish, and they have frequently appeared 

 recently in different papers. They are, how- 

 ever, not quite correct, in that the malaria- 

 bearing mosquito {Anopheles) does not occur 

 in Barbados and it is generally believed that 

 no case of malaria has ever originated in this 

 island. 



" Millions " eat the larvae of mosquitos and 

 many forms of aquatic animal life. The 

 permanent pools and small streams which 

 would be the natural breeding places of the 

 Anopheles mosquito are inhabited by " mil- 

 lions." Other mosquitos are able to main- 

 tain themselves in Barbados because they 

 naturally breed in water which is not in- 

 habited by " millions," but there is a possi- 

 bility that the absence of Anopheles in this 

 island may be due, wholly or in part to the 

 presence of enormous numbers of these small 

 fish. 



The Imperial Department of Agriculture 

 has introduced " millions " into Antigua, St. 

 Kitts-Nevis and Jamaica and they have been 

 taken to British Guiana and Colon. " Mil- 

 lions " are among the most active natural 

 enemies of mosquitos and in any malarial 

 country where they become established they 

 will be almost certain to exert a very con- 

 siderable effect on the prevalence of the 

 malarial mosquitos, because they naturally 

 inhabit the breeding places of Anopheles. In 

 any locality where it is possible to establish 

 " millions " in rain-water tanks, reservoirs, 

 fountains, etc., much relief may be had from 

 the mosquito nuisance. 



The "millions" of Barbados are closely re- 

 lated to the top-minnows found in different 

 parts of the United States, certain species of 

 which are well known as natural enemies of 

 mosquitos. Top-minnows from Texas have 

 been introduced into the Hawaiian Islands, 

 and similar fish have frequently been used in 

 stocking streams and ponds for the purpose 

 of reducing the numbers of mosquitos in 

 certain localities. 



H. A. Ballon 



Impebial Department op Ageicultdee 

 FOB THE West Indies 



THE ODONATA OF MEXICO 



To THE Editor of Science : In my article on 

 " The Present State of our Knowledge of the 

 Odonata of Mexico and Central America," 

 published in Science for November 13, 1908, 

 I have unintentionally omitted the Ohio State 

 University from the list of cooperating in- 



