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interesting fact, and possibly a bit of collateral evidence in favour of the feeler hypo- 

 thesis, that where this is the case the legs are eij^ht instead of six, and the first pair 

 actually perform the part of feelers: when we watch the spider, whose sense of touch 

 is so obvious and so exquisite as to have excited admiration in all ages, we cannot 

 resist the conviction that, whatever other function may be entrusted to them, the 

 anterior legs are certainly organs of feeling. In the Crustacea we have to deal with 

 other facts and another structure: the legs are ten instead of eight or sis, and none of 

 them are either homologically or analogically the substitutes for, or representatives of, 

 antenna^, since normal antenna; are not only present, but are always twice, and some- 

 times three or four times, as many as in tetrapterous hexapods. Physiologists have 

 theorized very differently on the functions of these multiplied antennae. Milne- 

 Edwards considers the outer or longer pair as auditory organs ; he is confessedly 

 influenced by the supposed auditory chamber situated at their base, and he leaves the 

 interior or shorter pair to be considered olfactory or feeling organs; but Mr. Spence 

 Bate, in a paper lately published in the 'Annals' (No. 91, dated July), attempts 

 exactly to reverse this theory, contending, at great length, that the long exterior 

 antenna; are olfactory, the short interior ones auditory. Recent observations on the 

 living prawn {Palcftnon serratus) throw grave doubts equally over the generally received 

 view of Milne Edwards and the more elaborately argued, but more hypothetical sug- 

 gestion of Mr. Spence Bate. The antennal system of the prawn, although familiar to 

 the Crustaceologist, is perhaps not equally so to the general entomologist, and therefore 

 a brief description may not be out of place: the antennae are eight in number; con- 

 ventional and technical usage — whether wisely or not who shall say? — reduces them 

 to four: all are alike in structure, filiform and multiarticulate ; the exterior on each 

 side is the longest; the other three are of different length, are united at their base, 

 and are seated on the summit of a stout triarticulate footstalk. These three antennae are 

 invariably called 'branches' by the closet-naturalist; but the field-naturalist and the 

 physiologist mustof necessity call them 'antennae;' first, because not apprised of the con- 

 ventional usage respecting them, and, secondly, because, reasoning on the fact that the 

 branches of the antennae in true insects are never articulated, they do not expect to find 

 multiarticulate branches in the antennas of any animal. It may be very easy to argue 

 that the two longest of these many-jointed threads ought to be ears, and that the other 

 six ought to be noses, or vice versa, but seeing how precisely they agree in structure, — 

 seeing that the microscope fails to detect a difference, — and seeing, moreover, as we shall 

 see, that there is no perceptible discrepancy in the mode in which the living animal may 

 be said to handle these weapons of perception, it is very difficult to convince the matter- 

 of-fact mind of a naturalist that the argument is conclusive or the hypothesis established. 

 Thanks to Mr. Warington, the prawn is now as easily kept in confinement as the rabbit 

 or the guinea-pig, and we have every opportunity of observing how he behaves himself 

 both under congenial and adverse circumstances: under every condition the antennae 

 are constantly in action ; always also acting in concert, as by a common impulse for a 

 common object. Mr. Warington, in his admirable account of the prawn, in a late 

 number of the 'Zoologist,' says that he considers the sense of smell as residing most 

 strongly in the antennae ; and he relates, far better than I can, the wonderfully 

 beautiful manner in which the prawn appears to hunt its food by scent. The following 

 experiment I have often tried, and invariably with the same result: — Fix on the point 

 of the usual feeding-fork a small piece of meal; plunge it in the sea-water near 

 the prawn, but not near enough to touch or disturb him ; then draw it through the 



