Odoriferous Glands 43 



to Laniatores, that these organs were odoriferous glands'. But this statement was overlooked 

 also by Krohn who in 1867 specially examined these organs and found that they were 

 glands, without, however, recognizing their special function". Thorell («) very properly 

 utilized the fact that in some cases their openings are visible, whilst in other cases they 

 are apparently wanting, as a character for the distinction of genera within the sub-order 

 Palpatores. In 1879 Simon {h, p. 121) expressed his opinion thus: "il pai-ait probable que 

 ces organes speciaux secretent le liquide odorant particulier aux faucheurs," to which he 

 adds on a subsequent page (p. 133) : " plusieurs possedent aussi, comrae moyen de defense, 

 un liquide odorant excrete par les orifices lateraux dont nous avons pai'le : chez le Phalangium 

 Opilio cette odeur rappelle celle du brou de noix." In the same year Sorensen {h, pp. 179 — 

 185) showed that these organs in Laniatores are odoriferous glands, and stated that when 

 the animal is irritated, the glands often — together with the urine — secrete a liquid of a strong 

 yellow colour caused by small drops of oil held in suspension in it, and of a sharp odour 

 reminiscent of horse-radish, which irritates the eye of an observer examining the animal with 

 a magnifier. Loman who was acquainted with Sorensen's anatomical investigation stated 

 subsequently {a, p. 15) that he must leave the question of their function undecided as 

 regards Phalangioidse, but as both Latreille and Simon have stated in the passages above 

 quoted, that the animals of this family also develop an odour, there can be no doubt as 

 to the function of these glands. They do not secrete oil in Phalangium, at least not in 

 Ph. parietinuvi. 



We have mentioned the mistakes committed by earlier writers with regard to the 

 odoriferous glands in the common harvest spiders, because one of them lias been repeated 

 with regard to Cyphophthalmi, the openings of the odoriferous glands together with a small 

 surrounding space having been regarded by all previous authors as " stalked eyes." The 

 mistake is not unnatural, because the openings of the glands are placed at the top of a 

 pair of pi-otuberances of varying height, of nearly conical shape, our " coni foetidi " ; the 

 tops of these protuberances are generally rounded, and the spot where the opening is placed, 

 is encompassed by a small more or less convex area, whilst the surrounding space is often 

 rather depressed ; in Siro and Parasiro this area is semiglobular and shiny and looks very 

 much like an eye, when not very carefully examined. Besides, the great majority of the 

 genera of the two other sub-orders of Opiliones which are better known, have their real 

 eyes placed on protuberances, generally both on one and the same, but in some cases each 

 eye is placed on a separate protuberance. To this must be added that the two genera 

 of Cyphophthalmi which have been known the huigest, Siro and Parasiro, are both without 

 real eyes. In Stylocellus, which does possess a pair of eyes, they were overlooked by 

 Westwood, who established the genus. Thorell, who discovered them and therefore counted 

 two pairs of eyes in Stylocellus, had his suspicion roused at this number so unusual in 

 Opiliones, but unfortunately he directed the suspicion against the real eyes, with regard to 

 which he of course found it not justified. He expresses himself thus in speaking of S. Beccarii 

 (c, p. 26, the note) : " Maculas duas succini coloris, quas oculos sessiles judico, foramina 



' He says with regard to the liquid : " su olor particular eu peligro." 

 y muy fuerte, que imita al del Acido nitrico 6 al de las - These glands are often (in Phalangioidre) called the 



avellanas raucias. La anatomia de algunos individuos vivos glands of Krohn, but this name ought not to be used, not 



nos ha probado que este liquido estaba contenido eu dos only because Gervais had recognized their true nature many 



bolsas ovales, una a cada lado del cefalotorax, y que salia years before Krohn, but also because their function is now 



cerea de la cabeza cuando el animal se hallaba persequido 6 known, and they ought to be named after that. 



6—2 



