Dr. J. Young on the Malacostraca of Aristotle*. 247 



Carabi have these members numerous ^^ (iv. 2. 10). " It [? Cara- 

 hm~\ receives the water by the mouth (pushing aside with the 

 sheaths), and discharges it by the upper apertures of the mouth 

 (covering with the sheaths those by which it entered); and these 

 [apertures] are straight below the eyes [and when it has received 

 the water, it covers the mouth with both the sheaths, and thus 

 squirts out the sea] " (iv. 3. 3). The clause [ ] is by Schneider 

 considered of later date — a marginal interpolation; it seems 

 further as if those marked ( ) were also annotations or attempts 

 to connect with the acts described the constant motion of the 

 branchioid structures ; for, besides the awkward elliptical form 

 of both, the latter separates, very inelegantly, ovtol from roi)? 

 av(o 7r6pov<; tov (7T6fiaTO<i, to which it evidently refers. In the 

 first passage, the text, as amended by Schneider, is adopted on 

 account of the support it derives from the quotation De Resp. ; 

 though there is still a little difficulty left in the relation of ol re 

 KapKivoL Kol ol Kapa/Sot, to the rest of the sentence, and the re- 

 moval from its right place of an important part of the process 

 irapa ra ffpay^^^co^r). The subsequent insertion of the illustrative 

 genera as a note is probable from the structure of the sentence, 

 of which they cannot originally have formed a part. Without 

 entering into a minute analysis of these passages, it seems evi- 

 dent that Aristotle was aware of the return of the water by the 

 external efferent apertures, which he wrongly thought to open 

 into the mouth, and therefore, equally wrongly, attributed the 

 expulsion to the coincident approximation of the maxillee. The 

 respiration in Crustacea is the subject of an excellent paper by 

 Milne-Edwards (Ann. d. Sc. Nat. ser. 2. t. xi. Zool. p. 129), in 

 which the part played by the maxillary appendages is experi- 

 mentally demonstrated. The repetitions, obscurity, and inele- 

 gance of chap V. induced Schneider to regard it as not authentic ; 

 but he seems to have been led to this opinion by the attempt to 

 find in it the true theory of respiration, which, I have shown, it 

 could not contain. More likely is it that additions have been 

 made, either by Aristotle himself, as more information was ob- 

 tained or new opinions formed (thus the first pair of jaw-feet 

 are in it described as sheaths), or by zealous commentators 

 anxious to make clear concise statements of facts with which 

 they were profoundly unacquainted. The extension of the in- 

 flux and efflux of water to the whole group depends upon a dis- 

 puted reading, kolvov Se itclvtcov totjtcov iarlv oSovra? Trdvra 

 ep^etv Svo, or tovto iarLV oSovra^; re (Hist. iv. 2. 10) : the 

 latter seems the more probable version ; but, as we have only 

 probabilities to guide us, their discussion is fruitless and un- 

 necessary. 



The feet are ten in number, in all but Kaph Kvcf)'*], whose 



