Aug. 1, 1S70.J 



HAKDWICKE'S SCIENCE-GOSSIP. 



183 



in the great Kentucky caverns, far removed from 

 access to the solar ray ; the other is the Myxine 

 {Gastrobranchus ccecus), a small eel-like animal 

 found on our own coasts, where it is parasitic on 

 larger fish, clinging to them by means of its mouth, 

 which is furnished witli a powerful sucker, and 

 extracting their juices for its own benefit. 



It is, however, among insects that natural 

 blindness most frequently occurs, and the beetles 

 supply us with the greatest number of examples. 

 Some of them are destined to spend their existence 

 deep in the bowels of the earth, and these are 

 almost invariably without eyes. The caves near 

 Adelsberg have been thoroughly investigated by 

 Professor Schiodte, who found, among others, a 

 Carabid, Aphcenops Lescheiiaultii, a Staphylinid, and 

 two Sylphids, — Adelops Pyrencens and Pholemon 

 Qi/erii/iaci, — all with names ugly to pronounce, but 

 unfortunately without any English equivalents. 



Indeed, wherever the conditions of life are such 

 that the animal rarely or never comes in contact 

 with the light of the sun, the eyes are almost 

 certain to be obsolete ; or, at any rate, so imperfect, 

 as to be practically useless. Such is the case with 

 Anommalus obscurus among the Carabids, with the 

 xylophagous or wood-boring Langelandia anophtlial- 

 ma, and with another beetle widely separated from 

 these in habit and structure, — Claviger foveolatus, 

 whose strange fate it is to live — where few, perhaps, 

 of our readers would think of looking for it — in the 

 interior of the nest of the yellow ant {Formica 

 flava) , 



Among the Physapods, or Thrips, the eyes are 

 usually conspicuous enough ; one species, however, 

 exists in which these organs are altogether wauting, 

 ■ — the Aptiuothrips ritfa of Halliday. It is a British 

 species ; and I believe little or nothing is known of 

 its habits. The order of Thysanures (Spriugtails), 

 in which also the eyes are for the most part suffi- 

 ciently evident, affords a blind species discovered by 

 Schiodte in the caves of Adelsberg. 



In the Neuropterous order, the same which em- 

 braces the Dragon-flies and May-flies, to whom may 

 well be applied the Homeric title of ox-eyed 

 (Bob]pis), so large are their organs of vision, is placed 

 the curious family of Termites, misnamed White 

 Ants. Like ants however, a termite community is 

 divided into castes, each of which has its distinct 

 duties assigned to it ; and of these the workers 

 and soldiers are totally blind. Erorn our point 

 of view the idea seems eminently absurd, of engaging 

 a host of workmen to build a city, or of employing 

 an army of warriors to defend a territory, none 

 of whom can boast of an eye to guide them in 

 their toils, or to aid them in watching the move- 

 ments of the enemy. But in fact this is one of 

 the many cases in which analogy utterly fails, 

 when comparisons are attempted betwen the func- 

 tions of the lower animals and those of the lords 



of creation. There are no mightier or more dura- 

 ble structures on the face of the earth, looking 

 to the relative size of the builders, than those raised 

 by termites ; nor are there any animals existing 

 better organized, or fitter to take the offensive when 

 needed than these " born gladiators," as the llev. 

 J. G. Wood aptly designates them. Termites, 

 whether they see or not, are essentially shunners of 

 light ; for, although denizens of the sunniest regions 

 of the globe, they never by choice expose themselves 

 to the solar ray, invariably travelling either under 

 the soil, or through passages and tunnels, which 

 they themselves construct with marvellous rapidity. 

 The true Ants belong to the Hymenopterous order : 

 in no case are their organs of sight very well deve- 

 loped, the number of separate facets in their com- 

 pound eyes rarely exceeding fifty, whereas most 

 insects count them by thousauds. But many of the 

 tropical ants are either absolutely blind, or furnished 

 with mere specks by way of eyes. Among them 

 may be named the species of Eciton, which traverse, 

 in countless myriads," the forest wastes of South 

 America, carrying death to every creature that 

 cannot get out of their way in time ; and the Driver 

 {Anomma arcens), which is equally prolific, and 

 equally destructive in Western Africa. None of 

 these curious insects can guide themselves on their 

 marauding expeditions by the faculty of sight, nor 

 do they ever see the prey 'which has the misfortune 

 to fall into their clutches. 



Blind spiders have been detected in the great 

 natural caverns of both Europe and America,andalso 

 various crustaceans. "In this country," observes 

 Gosse ("Romance of Nat. Hist."), "we possess at 

 least four species of minute shrimps, belonging to the 

 genera of Niphargus and Crangonyx, three of which 

 are absolutely blind ; and* the fourth, though it has a 

 yellow speck in the place of an eye, probably so. 

 All these have been obtained from pumps and wells 

 in the southern counties of England, at a depth of 

 thirty or forty feet from the surface of the earth." 



It is needless to carry our inquiries further, 

 as from this point the power of vision becomes 

 rather the exception than the rule ; whole orders of 

 animals living and dying without ever gazing on 

 the glorious luminary which bathes them in its light, 

 though doubtless they get as much enjoyment from 

 its life-giving rays as do creatures gifted with the 

 largest and most complicated organs of sight. 



Although the facts connected with natural blind- 

 ness among the lower animals have long been known, 

 it is only lately that the subject has been examined 

 from an anatomical point of view, at least as regards 

 the insects. This has now been done by a Erench 

 savant, M. C Lespes, who communicated the result 

 of his investigation to the Academie des Sciences of 

 Paris, in the year 1867, in a short paper, wherein he 

 observes : " The absence of the eye is not the charac- 

 teristic of a distinct family, several genera belonging 



