THE COLEOPTERA OF OLD CALABAR. 453 



it affords an example of the American famUy CEcliomjchis. The Erotylidae present some 

 resemblances between the two countries, as Bacne grandis to Dacne heros, &c. 



The general result of the whole undoubtedly is, that while by far the greater proportion 

 of the species of Old Calabar have the West-African facies, a small but still perceptible 

 proportion has the South-American facies. 



The natural inference from these relations is, that at some period the two continents must 

 have been united or contiguous ; but this is not a necessary sequence. For example, no one 

 will maintain that the Kentucky caves have ever been united or contiguous to the Carni- 

 olan caves ; and yet the relationship and resemblance of the eyeless Coleoptera found in 

 these two localities are greater than iu any two species which can be contrasted from Old 

 Calabar and South America. I am willing to assume for the present that Europe and North 

 America have been at some period united, and that the affinity between AnopUhalmm 

 BilimeUi and A. Tellhampfii may be explained, on Mr. Darwia's theory, by assuming 

 them to be the product of the same or of allied TrecU which have wandered into the caves, 

 and that the like conditions have impressed a like form on their offspring. This latter 

 assumption is of course not Mr. Darwin's ; for he repudiates the idea of physical conditions 

 making much, if any, impress upon life. I confess I am still a believer in that exploded 

 heresy. I can see no other way of explaining the existence of these allied blind insects 

 in caves so widely separated ; and if it applies to the caves, it may equally apply to any 

 district with well-marked physical conditions. May not, for instance, a North- American 

 Frionus, the same as, or closely allied to, a European species, have wandered southAvards 

 to the Brazil districts and produced a Polyoza, while its European fellow wandered into 

 Old Calabar and produced a Bonjcera'i that is, supposing the physical condition of 

 Brazil and Calabar to be the same, and that they have some resemblance m climate, 

 moisture, &c., as is, I believe, the case. This is indicated, inter alia, by the scarcity of 

 epigeal Tenebrionid^ in both. The distribution of that class of insects is cui'ious ; 

 Lacordaire thus states it :— " In the old continent, the whole of Africa, the borders of 

 the Mediterranean, and the regions in the neighbourhood of the Caspian Sea constitute 

 three great centres in which they abound. The East Indies and Australia only possess 

 a small number. In South America, the whole of Patagonia, the Argentine Republic, 

 Chili, Bolivia, and Peru are the only regions of this vast continent where they are 

 greatly multiplied. In North America, they begin to appear in the plains to the east 

 of the Rocky Mountains ; and their number goes on increasing in proportion as they 

 advance to the west. California and the still imperfectly explored regions of New 

 Mexico seem to be, in that continent, the special country of these insects. But the most 

 important fact to mention is, that, except a few Opatri, not one of these American forms 

 enters into the genera peculiar to the old continent, and vice versa. More than that. 

 North America and South America do not appear, so far as is yet known, to possess a 

 single genus in common. The non-epigeal Tenebrionidse are distributed according to 

 other laws. They are found everywhere, but more than anywhere else in the inter- 

 tropical regions of South America." So far as regards epigeal species, this is in ac- 

 cordance with what might be expected. Being apterous, their distribution must be 

 less extensive and more defined. A barrier, such as a great river or an arm of the sea, 



