352 



THE CRUSTACEA. 



^ 292. 



ed as a Penis. <'^ The length and mobility of this tail is such that it can be 

 used, with the Cirripedia, as a copulatory organ, and, being brought in 

 contact with the orifice of the oviducts, which is situated ou the mantle, 

 self-imprcguatioa may thus take place.* 



11. Female Crustacea. 



§ 292. 



The female genital organs of the Siphonostoma and Lophyropoda consist 

 nearly always of two long and sometimes flexuous ovarian pouches, situated 

 on both sides of the digestive canal. The oviducts pass backwards and 

 terminate on both sides of the end of the body by separate orifices, or by 

 a single genital opening on the median line. With those species whose 

 body has a tail, these orifices are not situated like the anus, at its extrem- 

 ity, but at its base. Very often, they serve as the outlets of the excre- 

 tory ducts of two caecal organs which secrete a viscous substance by which 

 the eggs are glued together in clusters or chaplets.^^' Not unfrequently, 

 there are hook-like or capsular appendages near the genital openings, for 

 the retention of these clusters.'-' But these are wanting with the Daphni- 

 oidae, there being in their place an incubating cavity, situated between the 



I 



5 Cuvier (M6m. loc. cit. p. 9, fig. 8) has taken, 

 witli Lepas, tiie testicles for the ovaries, and the 

 Fasa deferentia for the testicles. This error could 

 not be rectilied until the discovery of the true 

 ovaries (see liurjneister, Beitr. loc. cit. p. 33, 

 Taf. II. fij,'. It) ; Wagner, in Mailer's Arch. loc. 

 cit. p. 469, Taf. VIII. fig. 8 ; and Martin St. Jnge, 

 loc. cit. p. 21, PI. II. Lepas). It is more singular 

 to see Goodsir (Edinb. New Pliilos. Jour. ISio, Ju- 

 ly, p. 88, PI. III. IV. or Ann. d. Sc. Nat. I. 1844, 

 p. 107, 1*1. XV. C. or Froriep''s neue Notiz. No. 

 651, 1S44, p. 193), endeavor to confuse this ques- 

 tion by declaring the hermaphrodite animals nf 

 Halan us to be females which carry, in the cavity of 

 their mantle, dwarfish and abortively-fjrmed males. 

 Very probably those so-called males are parasitic 

 Crustacea, as Kulliker (Schweiz. Benks. loc. cit. p. 

 33) has supposed. 



1 The female genital organs are completely double 

 with tlie Ponellina, the Lernaeodea, the Ergasilina 

 and the Caligina ; see Nordinann, loc. cit. p. 6, 

 Taf. I. fig. 4, Taf. V. fig. 7, Taf. VI. fig. 10 (Lam- 

 proglena, Achtheres and Peniculus) ; Goodsir, 



Edinb. New Philos. Jour. July, 1842, p. 178, or Ann. 

 d. Sc. Nat. XVIII. 1842, p. 181 ; Krtii/er, Naturh. 

 Tidskr. I. PI. VI. or Isis, 1841, p. 194, Taf. I. 

 Tab. VI. fig. 4, C. ^Calis:us) ; and Ratkki, Nov. 

 Act. Nat. Cur. XIX. p. 14''5,Tab. XVII. fig. 2 (JDi- 

 chelestium). This last-mentioned author was the 

 first to notice the organs which, in various Crustacea, 

 secrete the viscous matter mentioned in the text. He 

 found them highly developed with the Nicotkoi 

 (loc. cit. XX. p. 106), where they extend, with the 

 ovaries, even into the wing-like appendages of this 

 parasite. The ovarian follicles of Ckondracanthus, 

 which are multiramose, differ very much from the 

 usual form {Rathki, Ibid. XX. p. 123, Tab. V. fig. 

 18). With the Cyclopidae, there is only a single 

 genital opening, although the ovaries and the or- 

 gans secreting the viscous matter, are double. But 

 with Argulus, the female genital organs are the 

 most simple, consisting only of a single ovarian 

 tube, opening at the base of the tail (Jurine, loc. 

 cit. p. 448, PI. XXVI. fig. 3).t 



^ Nordmann, loc. cit. p. 8, Taf. II. fig. 6 (Er- 

 gasilu-f). 



* [ § 291, end.] That the Cirripedia are not uni- 

 versally hermaphrodites, was first discovered by 

 Goodsir (Ed. New Phil. Jour. XXXV. p. 88), up- 

 on Balaniis balaenoides. The male is vei-y small, 

 and it is not strange that it before eluded observa- 

 tion. 



Darwin has made some researches, lately, witli 

 a similar result in some respects. E.xceptions to 

 the rule were found by this naturalist in the genera 

 Ibla and Scalpellum. With Ibla, the males lie 

 within the sac of the female, and have an elongated 

 body with a pedicle below. He has also observed 

 tliat, with these genera, there are both females 

 and hermaphrodites ; and in some hermaphrodites, 

 males have been observed so similar in general 



character to those of Ibla, that he considers them 

 to be true males of the species with which they are 

 connected. Being thus supernumeraries, he has 

 termed them complcmental males. As spermatic 

 particles were distinctly observed in them, their 

 male nature is clear, but it would not appear 

 equally clear that they really belong to the genus 

 and species with which they are connected. Facts 

 so singular require further research. See Darwin, 

 Monogr. &c. loc. cit. p. 207, 231. — Ed. 



t [ § 292, note 1.] For further details on the fe- 

 male genital organs of Argulus, with illustrations, 

 see Leydig, loc. cit. in Siebold and KoUiker''a 

 Zeitsch. II. p. 339, Taf. XIX. fig. 5, a. Taf. XX. 

 fig. 8, 10. — Ed. 



