S1EBOLD ON HECTOCOTYLUS. 93 



minences. Figs. 1-3 exhibit five or six such elevations upon 

 each side. Fig. 4, on the other hand, has ten upon each side. 

 Fig. 4 then differs from the three preceding figures only by the 

 increased number of the lateral elevations, and yet Madame 

 Power says (see Wiegmann's Archiv, 1845, vol. i. p. 378, or 

 Oken's Isis 9 1845, p. 610) of this fourth form, which she sup- 

 poses to be an embryo three days old, that from this stage 

 elevations like buds gradually arise, provided with a double 

 series of dark points, and that these are the commencement of 

 the arms and their suckers ; where, however, in fig. 4 these com- 

 mencements of the arms are supposed to be, I can by no means 

 comprehend ; for this body, described and figured as an embryo 

 three days old, reminds one only of the arm of a Cephalopod 

 with its double row of suckers. Had Kolliker chanced to see 

 these figures, he would certainly have still more strongly be- 

 lieved that the Hectocotylus actually leaves the egg in its proper 

 form. 



Now that Verany and H. Miiller have drawn attention to the ex- 

 ternal sexual differencesof the Cephalopoda, the different accounts 

 given by Aristotle of the sexual distinctions and functions of the 

 Octopus acquire an especial value, since Aristotle appears to have 

 been acquainted with the natural history and internal structure 

 of the Cephalopoda to an extent that we must even now con- 

 sider astonishing. From the following passages, which 1 here 

 extract verbatim from Schneider's translation (Aristotelis de 

 Animalibus Historic, book x.), Verany and H. Miiller, who have 

 produced a new phase in the history of Hectocotylus, will learn 

 with astonishment, that Aristotle may fairly contest with them 

 the priority of their discovery of the relation of the male Octopus 

 to the Hectocotylus-arm. In fact, in book iv. chap. 1, 6 (loc. 

 cit.) 9 it is thus written : " Polypus (such is Aristotle's inva- 

 riable designation for Octopus) brachia sua ad officium cum 

 manuum turn pedum accordat: namque duobus, qua? supra 

 os habet, admovet ori cibum. Postremo autem omnium, est 

 hoc inter cetera acutissimum et solum aliqua parte candidum in 

 dorso (vocatur autem dorsum pars brachii laevis a qua prorsum 

 acetabula collocata sunt) et in extremo bifidum hoc igitur ad 

 coitum utitur." 



In the fifth book, chap. v. 1, we find further: "Aiunt non- 



