848 



THE CRUSTACEA. 



S^ 290. 



and formed in the two lateral pouches of the stomach of the Astacus fluvi- 

 atilis.'-^^ As they are not observed during the whole year, but only just 

 before the moulting, and as, when this process occurs, they pass from the 

 cast-off stomach into the cavity of the new one, it may be inferred that 

 they are in some way connected with the act of ecdysis, and that if the lateral 

 pouches of the stomach secrete from the blood the excess of calcareous 

 salts, it is in order that these last may be subsequently used for the for- 

 mation of the new shell/-' 



The caustic, brown fluid, which most Myriapoda, when touched, emit from 

 a row of orifices situated on the sides of the segments of the body [Fora- 

 mina repuguatoria), and which exhales an odor like that of chlorine, is 

 secreted by small, pyriform, glandular follicles, situated immediately 

 beneath the skin. Its use is, perhaps, for the lubrication of the articula- 

 tions of the segments of the body.''^' 



In the following chapter will be mentioned many other glandular organs 

 connected with the genital functions. 



CHAPTER IX. 



ORGANS OF GENERATION. 



§290. 



The Crustacea reproduce by Male and Female Organs, situated in differ- 

 ent individuals, and have, for the most part, copulatory organs. 



Nevertheless, the Cirripedia form an exception in this respect, being 

 hermaphrodites ; while, on the other side, many Entomostraca differ from 

 the general rule, in their species being almost exclusively females, which 

 produce, during many successive generations, individuals exclusively of the 

 female sex, and only at long intervals, those of the male sex.^^' There is, 



1 See Suckow, loc. cit. p. 53, Taf. X. fig. 10, 11, 

 e. This author is mistakeu in supposing that those 

 green glandular bodies mentioned in connection 

 with the organs of hearing (§ 276), secrete the 

 " Crabs-eyes." See also Brandt, Medic. Zool. II. 

 p. 63, Taf. XI. fig. 8. 9, c. 



Ü For the nature of tliese crabs-eyes, see the re- 

 searches of Baer (MuUer's Arch. 1834, p. 510) and 

 Oe.sterlen, Ibid. 1840, p. 432. 



■f Treviranus (Verm. Schrift. II. p. 42, Taf. 

 VIII. llg, i,f.f. fig. 5, d. e.) has regarded these 

 organs as respiratory with Julu.i, while Savi (Isis, 

 1823, p. 218, Taf. II. fig. 1, 13, 14, a. b.), and 

 Burmeister (Ibid. 1834, p. 136, Taf. I. fig. 1, a. a.) 

 have well perceived that they are cutaneous glands. 

 According to fVai^a (Revue Zool. 1839, No. 3, p. 

 76, or ill fyiei^mann^s Arch. 1840, II. p. 350), 

 Poli/Je.imun, Pliitijuliis, atid Geup/iilus electri- 

 ciis, have, upon the si les of the body, analogous 

 glauds, out of which this last Myriapod emits a 



* [ § 239, note 3.] These odoriferous glands 

 have been successfully studied by Leidy (Proc. 

 Acad. Sc. I'hilad. 1840, IV. p. 235) with Julus. 

 tiere, they consist of a globular body or sac, with 

 an elongated conical neck, and resemble in form a 



luminous liquid. Brandt (Recueil, &c., p. 154, 

 157) has observed, with Olomeri.s, that these fol- 

 licles are situated, in pairs, on the dorsal surface 

 of each segment of the body.* 



1 This is so with the Daphnioidae, Cypridoidae, 

 and Apodidae. In the second of these groujis, the 

 males are so rare, that these Entomostraca have 

 been taken for hermaphrodites, and Straus (loc. 

 cit. p. 52, PI. I. fig. 15) has said that if this was 

 really the case, he regarded as testicles two long 

 cylindrical problematical bodies which he had ob- 

 served with all the females of Cypris. In the 

 genus Apiis, no individuals which can with cer- 

 tainty be regarded as males, have been found. 

 Berthold (Isis, 1830, p. 693) has taken the 

 red ampullae found witli these Crustacea for 

 testicles ; but, as I have already remarked, these 

 ampullae are only branchial lamellae filled with 

 blood during the dying of the anin ^l. (See § 286, 

 note 5.) 



florence flask with the mouth drawn to a point. 

 This sac is composed of a basement membrane 

 lined with a single layer of secreting cells. Tlie 

 neck of the glands has muscular bands. — Ed. 



