that the Carolina Wrens ( ihryothorus ludovicianus ) in Florida differ 

 in their songs from those of Ohio. The little bunting of Sweden, 

 Norway, Schleswig-Holstein and Denmark sings differently from that of 

 Eastern Europe (Solomonsen, 1935)- Geographical voice variability has 

 also been established for the pika, various Fringillidae, tits, night- 

 jars, and many others (Thieckel, 196l; Stadler, 1917? 1930; Thoenen, 

 1962; Peterson, 19^1 ). Instrumental sounds are also subject to geo- 

 graphical variability, as they actually have the same functions. Ac- 

 cording to Blum and Young (1958), the drum roll of the black wood- 

 pecker in Holland lasts 3-5 seconds, and in Germany - 1.5 seconds. 



Among insects and amphibians, the voice apparently is hardly used 

 at all as a marking signal of small intraspecif ic groups (Blair, 1955, 

 1956; Frings, 1958). This is mainly due to their morphologically im- 

 perfect vocal apparatus and a lower organization of higher nervous 

 activity. In these groups the voice is apparently mainly used as an 

 isolation mechanism in higher taxonomic divisions (species and subspecies). 



Among insects and amphibians there is widespread nonadaptive geo- 

 graphical voice variability, which does not include any "marking" prop- 

 erties but is related to the general influence of climatic and other 

 landscape factors on the metabolism, and, consequently, on the voice as 

 well. In recent years there has appeared much data on the nature of 

 the climatic conditions influencing the voice of insects (Hukusima, 

 19^8; Harz, 1956), amphibians (Blair, 1955, 1958), and even birds 

 (Heyder, 195^5 Sick, 1939; Peitzmeier, 1955; Schwan, 1921-22). Under 

 the influence of temperature and humidity there occur changes in the 

 frequency characteristics, intensity, and even qualitative character of 

 individual syllables. But in birds the changes usually affect the 

 rhythm of the singing (Scheer, 1952; Thorpe, 1961). In this case we 

 consider the dependence of the voice on natural conditions a particular 

 feature of the general phenomenon of ecological-geographical isomorphism, 

 the idea of which, in its application to animals, was elaborated by 

 G.P. Dement' ev (19^8, 1951). 



Geographical voice variability in insects is a subject which has 

 occupied many investigators. A. Faber (1953) was one of the first to 

 establish this phenomenon. H. Jacobs (1957) observed differences in 

 the voices of insects of the locust family in Munich and the Tyrol. 

 Pierce (19^8) described the geographical voice variability of Memob ius 

 fasciatus . Highly interesting and informative work on amphibians as 

 carried out by Blair (1955-I962). A good review of the cases mentioned 

 in the literature can be found in the works of Schwartzkopff (1962). 



But the geographical variability of voice not only perfects itself 

 in the process of evolution - it also exercises an ever- increasing in- 

 fluence on the processes of form and species formation, acting as an 

 isolation mechanism. In this respect the coincidence of geographical 

 voice variability within species and subspecies is of considerable 

 interest. 



