110 



HARDWICKE'S SCIENCE-GOSSIP. 



stances. This is disposed of inside the said nest, 

 being often masticated and the juice extracted by 

 the workers, and then given in an inspissated form 

 from their mouths to the young grubs, which are in 

 general tended by their nurses with the greatest 

 care. It is indeed very curious to watch tliis feed- 

 ing process ; but to proceed. 



Under date Nov. 7tb, ISGG, I find in my luituial 

 liistory note-book as follows : — Mainpuri. This 

 morning as I was walking across the " Oosur," or 

 waste plain, wliere it was very sandy, being cut 

 into small ravines, and clollied only here and there 

 with fine grass disposed in clamps, thus forniing 

 little hillocks of sand blown by the wind, and ar- 

 rested in its course by the grass, I came across a 

 long line of ants, travelling four deep, some coming 

 empty, and others laden each with one grass-seed 

 on their way home. 



I followed up the procession to the nest, which 

 was subterranean, and at the mouth of which on the 

 level plain there was no trace of elevation caused 

 by the soil brought up from below, owing to the 

 habit of these ants of taking each grain of sand to 

 some distance along their road, and depositing it on 

 one side or the other. 



There may liavc been five or six entrances to the 

 nest, in and out of which a prodigious number of 

 ants were passing, the species of which has been 

 described by Dr. Jerdon. They were of a medium 

 size, shortish bodies, and of a reddish-brown colour, 

 • — Podomyrtiia rufo-nigra, Jerdon. Around the 

 mouth of the nest, forming a circle of perhaps 

 eighteen inches in diameter, was a space beaten 

 flat, and kept clear by these said ants, from which 

 radiated in every direction thirteen roads, each 

 about four inches in width for about 30 to 40 yards, 

 wlieu they branched off and became narrower, being 

 ultimately lost amongst the grass roots. These 

 paths were fairly straight ; they did not cut through 

 elevations, but M'ent round them. 



From a careful examination, it appeared that they 

 had been cleared of all obstacles, such as small 

 stones, twigs, &c., but that their smoothness re- 

 sulted only from the tread of countless feet. 



The bearers of burdens took the seeds into the 

 nest, which I did not dig up, and certainly stored 

 them there, after having prepared them, probably by 

 tlie removal of a portion of the outer husk. Of 

 tliese Imsks there were large collections near the 

 entrances to the nest, all carefully set aside by the 

 ants. 



In times of famine, 1 am told, not only are the 

 nests rifled of their grass-seed stores, but these 

 heaps of apparent husks are collected and ground 

 with otlier grain to eke out a subsistence. 



This kind of grain has a name, " Jurroon," derived 

 from " Jharna," to sweep, literally, sweepings. I 

 much regret that I have not preserved specimens of 

 this " Jurroon," for it is very unlikely that the ants 



after taking it to their granary, should again throw it 

 out, and yet, if grainless, what benefit could there be 

 in eating it ? The season of the year when I observed 

 them (November) is the beginning of the cold wea- 

 ther, and no rain would probably fall (excepting a 

 little at Christmas) till next May or June. Later 

 on seed would be rare ; and how the nest fares at a 

 time when floods of water often pass over the plain 

 I cannot conceive. 



It is clear that some escape, and we know with 

 what prodigious rapidity these colonies increase. 

 But these jottings have been recorded merely to 

 show how this species of ant store grain against 

 a time of scarcity, and fully bear out the. state- 

 ment in the text with which I commenced this 

 paper. 



MICROSCOPY. 



PiTCHSTONE, PoBPHYRiNE, &c. — One of the most 

 interesting of volcanic products to the micro- 

 scopist is the variety of pitchstone found in the 

 Isle of Arran. When thin sections of this material 

 are examined with a two-thirds or half-inch objec- 

 tive, beautiful dendritic forms will be found perme- 

 ating the vitreous mass. The casual observer is 

 apt to declare that these frond-like forms are fossil 

 mosses, arid is unwilling to believe that they have 



Fig. ~1. Section of Pitchstone. 



a crystalline origin. 'I'he pitchstone from the Isle 

 of Arran differs from obsidian, in containing a 

 variety of crystalline minerals ; the beautiful den- 

 dritic forms are produced by the acicular crystal- 

 lization of pyroxene. Tlicse crystals are cither 

 isolated or combined ; in the latter condition, they 

 appear like microscopic ferns, fronds, or tufts of 

 Batraeliospermum entombed in glass. The trans- 

 parent material in which these crystals occur 



