m 



total length of windings being almost incalculable, and even the 

 direct distance from the entrance to the termination extending many 

 miles. The temperature of these inland galleries is uniformly 59° 

 of Fahrenheit all the year round ; and a current of air is very per- 

 ceptible near the mouth, proceeding outwards or inwards according 

 as the temperature of the external air is greater or less than that of 

 the subterranean region. The air within is uniformly pure, even exhi- 

 larating ; and this is attributed in a large measure to the great beds 

 of nitre which disengage oxygen during the formation of nitrate of 

 lime. The general boundaries of the caverns are of limestone. 



Of the mammiferous animals described as inhabitants of these 

 caverns, there are two species of bat and one species of rat, the 

 latter being confined to, and characteristic of, the locality. If not 

 blind, its organs of vision are very defective. 



Two species of fish were lyjticed, of one of which, Amblyopsis 

 spelcEus of Dekay, specimens wore exhibited. It is totally blind, 

 possessing not even rudimentary organs of sight, dissection having 

 shewn that the optic nerve, and other essential parts, are wanting. 



Of the crustaceous tribes a blind cray-fish, Astacus pellucidus of 

 Tellkampf, was exhibited. The peduncle of the eye exists, but the 

 actual organ of sight is absent. The observance of this eyeless 

 peduncle had misled some observers into the belief that the creature 

 was not blind. 



Various kinds of arachnides, of true insects, and of aniraalcular 

 species, the majority of them quite blind, were then noticed in the 

 order of their position in systematic arrangements. 



The author concluded by referring to the difficulties which beset 

 the theoretic question, as to whether these creatures were blind from 

 their creation, or whether certain species, originally endowed with 

 sight, had wandered by some mischance into those darksome depths, 

 and in the course of ages had lost the organs of a sense, the func- 

 tions of which they could no longer exercise. 



The following Gentleman was duly elected an Ordinary 

 Fellow : — 



Gr^me Reid Mescer, Esq., Ceylon Civil Service. 



The following Donations to the Library were announced:— 



Memoirs of the Royal Astronomical Society. Vol. XXI., Parts 

 & 2. 4to. — From the Society. 



r2 



