Second German Xorth-Fular Voyage. 197 



Venezuela and Surinam . lS°-66 & 21°-32 E. ( = 73°-98 & 79°-97 F.). 



Bahia and Pernambuco . 18°-66 & 22°-64 R. ( = 73°-98 t 82°-94 F.), 



Singapore 18°-66 & 23°-08 11. (= 73°-98 & 83°- 93 F.), 



Fiji Islands 18°-66 & 23°-o2 R. ( = 73°-98 & 8-4°-92 F.), 



Tahiti 18°-66 & 22°-64 R. ( = 73°-98 & 82°-94 F.), 



ilanilla 20°-88 & 23°-52 E. (= 78°-98 & 84°-92 F.). 



From the temperature-observations made by Prof. Carl 

 8emper in the sea surrounding the Philippines, which he has 

 been kind enough to place at my disposal for these com- 

 parisons, I extract the following : — 



On the 26th of June 1861, near Anhuplate, between 10 

 o'clock in the morninoj and 10 o'clock in the evenino- 



the temperature of the air varied between 20*^-6 k 22°- 9 E. ( = 78°-35 



& 83°-5 F.), 

 the temperature of the surface varied between 21°-3 & 21°-8 E. 



( = 79°-9 & 81°-05 F.). 



At the same place on the same day the temperature at 



5 fathoms was 21°-5 E. (==80°-4 F.) at 10 a.m. 

 17 „ 21°-4E. ( = 80°-15F.)at2-30p.M. 



22 „ '21°-4 E. ( = 80°-15 F.) at 3 p.m. 



5 „ 21°-o E ( = 80°-4 F.) at 5 p.m. 



Thus, at the depths here cited, the temperature differs very 

 little from that of the surface, ju.?t as in the northern icy sea. 



I suppose that the nearly uniform temperatiu-e in which the 

 high-northern marine animals live is one of the chief causes of 

 the considerable size by which, according to numerous observa- 

 tions, they are distinguished from individuals of the same 

 species in temperate regions ; for, at the bottom of the icy sea, 

 species which from their nature can thrive in a low tempera- 

 ture are but little if at all exposed to those distui'bances which 

 the greater oscillations of temperature produce in the vital con- 

 ditions of the animals of more temperate seas. The organs can 

 consequently perform their functions in a more uniform manner 

 (so far as these are dependent on temperature) than in indi- 

 viduals of the same species which inhabit, for example, the 

 middle and higher regions of the Xorth Sea and the Baltic, 

 where the differences between the lowest and highest tempera- 

 tures of the water amount to 10°-lo° R. ( = 22°-5-33°-75 F.), 

 or sometimes even more, as has been ascertained by H. A. 

 Meyer * for various points in the western basin of the Baltic, 

 and by myself for two places in the North Sea off the German 

 coast t- 



* ' Untersuchungen liber physikalische Verhaltnisse des westlichen 

 Theils derOstsee ' (Kiel, 1871 )/§ 27. 



t Zeitschrift fiirwissenschaftliche Zoologie, Bandxxi.1871, pp. 301, 302. 



