174 Recent Literature. [a^HI 



sota Academy of Natural Sciences. The entire expense of the expedition 

 was borne by Mr. Menage, and its results were donated to the Academy 

 of Sciences." In the present brochure we have the first fruits of this 

 praiseworthy enterprise, sustained by Mr. Menage. " During the stay of 

 two years and five months in the Philippines " seventeen of the islands 

 were visited. Reference is made to the " careful series of measurements 

 of more than four thousand " specimens of birds, which will appear in 

 their final report, taken for the purpose of showing " the relative amount 

 of individual variation in the representatives of those genera which 

 display a strong tendency to develop local species as compared with other 

 genera which show no such tendency." 



In the present preliminary- paper 36 species of birds are described as 

 new, and new localities are given for 226 species previously- recorded from 

 these islands. Important notes are given on some 40 species previously 

 d'iscribed from the Philippines, supplementing the previous more or 

 less incomplete descriptions, or treating of questions of nomenclature, 

 including remarks on the Dicceum trigonostigma group as represented in 

 these islands. The final report on the results of this important expedition 

 will be awaited with interest. — J. A. A. 



Merriam's Laws 'of Temperature Control of the Distribution of Land 

 Animals and Plants.' — In his recent Vice-Presidential address before the 

 National Geographic Society of Washington, Dr. Merriam has given the 

 results of his long-continued investigations of the influence of tempera- 

 ture in controlling the distribution of animals and plants over the earth's 

 surface. Investigations made by botanists tend to show that plants 

 require a certain amount of heat — the amount varying of course with 

 the species — to reach a given stage of development, as leafing, flowering, 

 the maturation of seed, etc. This quantity is computed on the basis of 

 the average temperature of each day which reaches the minimum required 

 for the functional activity of the particular species in question. As Dr. 

 Merriam states it, " the substance of this theory is that the same stage 

 of vegetation is attained in any year when the sum of the mean daily 

 temperatures reaches the same value, which value or total is essentially the 

 same for the plant in all localities." Reasoning from this. Dr. Merriam 

 observes : " If it is true that the same stage of vegetation is attained in 

 different years when the sum of the mean daily temperatures reaches the 

 same value, it is obvious that the p/iysiological constant of a species must 

 he the total quantity of keat or sum of positive temperature required by that 

 species to complete its cycle of development and reproduction.'''' lie has 



* Laws of Temperature Control of the Geographical Distribution of Terres- 

 trial Animals and Plants. Annual Address by Vice-President Dr. C. Hart 

 Merriam. Nat. Geog. Mag., Vol. VI, 1894, pp. 229-238, pU. xii-xiv. 



