1880.] 15 g 



)N THE DISTEIBUTION OF DAM ASTER, WITH DESCRIPTION OF A 



NEW SPECIES. 



BY GEORGE LEWIS. 



For the study of certain forms of Coleoptera -which are limited in 

 heir distribution, the fauna of Japan is convenient, inasmuch as the 

 ountry covers over fourteen degrees of latitude, and the greatest 

 ireadth of unbroken land is barely five degrees in the widest part, 

 'he Archipelago is cut up into sections by dividing seas and straits : 

 q the north by the Tsugar Strait, in the south by the incursions of 

 he inland sea, while the main island in latitude 35° is geographically 

 auch broken up by the Owari Bay, Biwa Lake, and Wakasa Bay, and 

 ver this last line many of the southern species do not pass. Let us 

 onsider the position which Damaster — an endemic form of Carabus — 

 akes in a country thus topographically divided, and see how changes 

 f climate modify varieties and create species. In Kushiu, the 

 outhern part, we find a large black species of nocturnal habits 

 leasuring 29 lines ; a species of such vigorous and substantial habit 

 hat we almost instinctively look on it as the father of every Damaster. 

 lie forests it inhabits are those with summers of sub-tropical heat 

 nd length, ushered in by heavy rains, with little thermal change day 

 r night. The trees there attain considerable height and girth, and 

 arough many groves the sun scarcely penetrates. A few miles north- 

 ward of this district, near the well-known volcano of Simabara — the 

 ummit of which is sometimes in mid-winter capped with snow — the 

 alleys are composed of decaying lava, and on such a soil the trees are 

 f more moderate growth, and easily penetrated by the cold winds of 

 tie higher altitudes. Here, although only a few miles from Nagasaki, 

 re great climatic changes, and we find D. Leivisi, a half-starved form, 

 o to speak, of D. blaptoides. We then pass considerably more to the 

 astward, but only \\ degrees north, to Hiogo. Again we find the 

 oil, climate, and vegetation correspond with Simabara, and the same 

 pecies of Damaster. Crossing the Biwa-lake-barrier into the Toko- 

 ama district we come to quite a different form of insect, and we need 

 ot look far for reasons of change : we find D. pandurus, a clumsily - 

 jrmed species, in which much of the elegance of the outline in the 

 enus is lost, and the elytral mucrones almost obsolete, and with these 

 hanges colour first appears. The winters of Yokohama are com- 

 paratively severe : snow not infrequent, and cold winds from adjacent 

 now-covered mountains continual, penetrating the forest lands, and 

 he soil becomes ice-bound, sometimes for days together. On a 



