6i8 



NATURE 



[April 28, 1898 



obtained being 6054. The 11 -inch Draper telescope has been 

 employed for photographically recording the satellites of Jupiter 

 undergoing eclipse, and variables of the Algol type. Mr. King, 

 who has been investigating the effects of differential refraction 

 and flexure on the form of the photographic images, has found 

 that an equatorial should never be driven on sidereal time, but 

 that satisfactory images have been obtained by photographing at 

 suitable hour angles with a mean time driving clock, the rate 

 being wholly corrected by the refraction in right ascension. 

 Experiments are now being made to introduce a flexure correc- 

 tion automatically. In this connection it is interesting to refer 

 to the work done by Dr. Ram beau. With regard to the other 

 departments under the direction of Prof. Pickering, we must limit 

 ourselves here to mentioning them : namely, the Boyden depart- 

 ment at Arequipa, where the new Bruce photographic telescope 

 has been erected, and the Blue Hill Obser%-atory, although they 

 have both been contributing valuable observations during the 

 last twelve months. 



THE NATURE AND HABITS OF PLINY'S 

 SOLPUGA. 



A LTHOUGH next to nothing is known of the past history 

 •^ of the spider-like creatures discussed in the following pages, 

 it is tolerably certain that since glacial times they have been 



Fig. I.— Indian Solpuga {Galcodes fntalis). — !., male ; kt, jaw of male seen from the side ; 2, female 

 2a, jaw of female seen from the side. (Figs, i and 2 reduced to three fourths the natural size ) 



confined in their distribution, so far as Europe is concerned, to 

 Spain, Greece and South Russia. Since, therefore, they were 

 certainly unknown to our British and Anglo-Saxon ancestors, 

 and probably also to the early Romans, it is not surprising that 

 the English language has no name for the group of which they 

 are members. To the ordinary Englishman they are spiders, 

 and as spiders or tarantulas they are usually described by 

 travellers who have come across them in India, Egypt and 

 elsewhere. The Greeks, on the contrary, who were doubtless 

 acquainted with the species inhabiting their own country and 

 Asia Minor, seem to have recognised them from the ordinary 

 spider, since they had a distinctive name for each of the two 

 groups. The spiders were called Arachne {,h.p6.xvr\) ; the 

 others Phalangium (cpaAdyywv), in allusion to their five pairs 



NO. 1487, VOL. 57] 



of long-jointed limbs. ^Elian, for example, tells how a country 

 in Ethiopia was deserted on account of the appearance of 

 incredible numbers of Scorpions and Phalangiums. But Pliny, 

 when quoting the same story, introduces Solpuga^ in place 

 of Phalangium. And since the latter is now used in systematic 

 zoology for a totally different group, namely for the so-called 

 Harvest or Long-legged Spiders, so abundant throughout 

 Europe, no further reason need be given for adopting Pliny's 

 name for the species now under discussion. 



So much by way of preface. But before leaving the ancient 

 history of the Solpuga, it may be interesting to mention a sug- 

 gestion that has been made to the effect that the Hebrew word 

 translated Mouse in the Old Testament referred to some sort of 

 Solpuga ; and that the sores, the emerods (haemorrhoids), from 

 which the Philistines suffered, resulted from the bites of these 

 creatures. In support of this supposition may be urged the 

 unmistakable resemblance to mice presented by some of the 

 smaller, dark-coloured, short-legged species, with their hairy 

 bodies and rapid movements, which occur both in Egypt and 

 Syria ; and the statements of travellers to the effect that at the 

 present time they inflict pamful bites upon people when asleep 

 in the desert at night. 



It is beyond the scope of the present article to deal with the 

 many points of interest connected with the anatomy of these 

 animals. Nor is it necessary to point out all the distinctive 

 features which serve to separate them from the true spiders, 

 the only members of the class Arachnida 

 with which they are likely to be con- 

 founded. Suffice it to say that the term 

 spider, doubtless a corruption of spinner 

 (sfHnster), is technically applied exclu- 

 sively to the familiar webspinners, and 

 that no silk glands exist in any members' 

 of the order Solifugee. 



The general form is well shown in the 

 annexed illustration depicting the male 

 (Fig. i) and the female (Fig. 2) of a 

 North Indian species called Galeodes 

 fat aits. As will be seen, the sexual 

 differences are very striking, the male 

 being both smaller and lighter in build, 

 with the head narrower and the jaws- 

 less bulky ; the legs, on the contrary, are 

 unmistakably longer. This correlatiort 

 between lightness of body and length of 

 limb points to much greater activity on 

 the part of the male, a superiority which 

 no doubt stands him in good stead at 

 the pairing time, when the female has a 

 habit, it is alleged, of killing and devour- 

 ing her less powerful mate. Again, in 

 addition to being smaller, the jaws of the 

 male (Fig. la) are always less strongly 

 toothed than those of the female (Fig. 

 2a), and are furnished on the upper side 

 with a peculiar organ of unknown func- 

 tion called \\\& flagelium. 



In both sexes, but especially in the 

 female, the jaws attain a development 

 unequalled elsewhere in the class Arach- 

 nida (Spiders, Scorpions, Solpugas, &c. ). 

 They are, in fact, admirably adapted 

 for the purpose of crushing hard-shelled 

 beetles and other insects. But they also- 

 have another duty to perform, namely, 

 that of digging ; for the females, at least 

 at the breeding season, excavate sulDterranean burrows for the 

 protection of themselves and their young. The process has- 

 been ol)served in the case of the species here figured. Choosing 

 a suitable spot, the female proceeded to cut away the earth rn a 

 circle with her jaws, then kicked away the loosened fragments, 

 with her legs, or scraping them together into a heap with the 

 palpi [the long front pair of legs], pushed the pile by main force 

 from the entrance of the burrow. At its opposite end the eggs, 

 about fifty in number and resembling a mustard-seed in size and 

 shape, were laid, and hatched about a fortnight afterwards. For 



1 This word is, perhaps, a corruption of Solifuga or Solipugna, which 

 seem also to have been in use. The former means a creature which flees, 

 from the sun ; the latter one that battles against it, and so hates or is in- 

 tolerant of it. 



