MOSQUITOS OF SOME PORTS OF CHINA AND JAPAN. 407 



half to one mile wide, between hills at the back and the sea, and so has a very long 

 sea frontage. The population in 1919 was 588,124, and the town is distant only 20 

 miles from Osaka, also on the coast, with a population of 1,400,000. There is ample 

 communication between the towns by steamers, trains and electric trams. 



Trade. — The main trade of the Empire centres in Kobe, steamers from all quarters 

 of the globe berthing there, after having, as a rule, first visited either Nagasaki or 

 Yokohama. 



Temperature and Rainfall. — These are practicalh- those of Yokohama. 



Water Siipplv.- — A piped sapph^ is everywhere laid on from reservoirs in the 

 mountains at the back of the town. 



Mosquitos. — The following species were obtained: S. alhopicta, A. {Finlaya) 

 togoi, A. {Finlaya) japonicus, C. tritaeniorhynchus, C.fatigans and A. hyrcanus, "the 

 larvae occurring in places similar to those in which they w^ere found in Nagasaki. 

 A species regarded by Mr. F. W. Edwards as C. pipiens, L., though the male genitalia 

 are not quite identical with those of European specimens, was here obtained for 

 the first time, breeding in similar places to C. faiigans, if not mixed with it. 



There seemed also to be a marked reduction in ^4. japonicus, for one specimen 

 only was obtained, though A. togoi occurred in great abundance. 



Yokohama. 



Yokohama is situated in latitude vS6^ 26' North and longitude 139° 38' East on 

 Tokyo Bay, 18 miles south-west of Tokyo. It stands on a plain shut in by hills on 

 either side. It is the sixth largest city in the Empire, with a population of 400,000 

 Japanese and 10,000 foreigners, who mostly reside in one quarter of the city. 



Trade. — Its natural excellence as a harbour has made it one of the two greatest 

 ports in the country, its imports and exports being second only to those of Kobe. 

 All the steamer lines from China, India and Europe converge at Yokohama, and it 

 is the first port of call for Trans-Pacific liners from the United States and Canada. 

 It is in direct communication with ports of the west coast of Mexico and Central 

 America, the ships of one of the large passenger lines, coming by way of the Panama 

 Canal, taking from 23 to 27 days in making the journey from Panama to Yokohama, 

 putting in at San Francisco en route. 



Temperature and Rainfall. — The seasons correspond to our own, the mean tem- 

 perature in the spring (March to May) being 55" F., in the summer (June to August) 

 73-9°, in the autumn (September to November) 60-6'', and in the winter (December 

 to February) 39°. The cold in winter is often severeh' felt owing to northerly winds. 

 The rainfall is about 70 inches annually. There is a heavy rainfall during the winter 

 and early spring months, and after an intermission of a couple of months, mild rains 

 fall with some constanc}/ in June. The latter rains, coming at a season when with 

 rising temperature mosquito activity begins to be felt, serve to keep possible breeding 

 places constantly full of water, a factor of importance as favouring at that season 

 the increase of mosquitos. At Kobe, and in the south, these rains are less constant. 



Water Supply. — A piped supply serves the whole city, but the collection of rain- 

 water in unscreened vats and barrels is general, there being a demand for it for the 

 dyeing of cloth. 



Mosquitos.- -The following were obtained: Stegomyia alhopicta, Aedes (Ftnlaya) 

 togoi, Culex pipiens, C. orientalis, Edw., and Anopheles hyrcanus. 



Stegomyia alhopicta. — The breeding places of this species were of the same t3-pe 

 as in Nagasaki, though the larvae were obtained less freely than in the south. They 



