"^.m 



THE HELMINTHES. 



127 



rior portion of the bodj/^ It has a great variety of forms, and from its 

 sheath arise two antagonistic muscles, which are inserted at its base/'^' The 

 spermatic particles, which are always motionless, have usually a cell-form, 

 or, at least, are never filiform corpuscles.^' For aiding the union of the 

 sexes during copulation, the males have lobular appendages, papillae, and 

 suckers, situated about the genital opening. Without doubt, the spiral pos- 

 terior extremity also of the animal, is often used for the same purpose. 

 Moreover, in many instances, there is secreted a wax-like substance in- 

 tended to fasten the two sexes together. ^'■'^ 



6 According to Leblond (loc. cit. p. 20, PI. III. 

 fig. 1), batti the male and female genital openings 

 with t'ilaria papilloma are quite near the oral ori- 

 fice. I have been unable to confirm this obs2rva- 

 tion, at least with Filaria attenuata, injlexo-cau- 

 data, and another species found in the thoracic 

 cavity of St urnus vulgaris. 



7 With Trichocephaius, and Trickosoma, the 

 penis is simple and very long, and, beside the mus- 

 cular sheath, has another wliich is membranous, 

 and sometimes covered with small spines pointing 

 backwards. This sheath, being folded outwards 

 when the penis is protruded, is comparable to a 

 Praeputium ; see Mayer, Beitr. loc. cit. Taf. I., 

 and JJujardiH, Hist. d. Uelm. PI. I.-IU. With 

 nearly all the other Nematodes the penis is double. 

 It is very long with Ascaris acuminata, brevi- 

 caudata, depre.isa, spiculigera, and Strongylus 

 paradoxus ; but is very short with Jscaris ew.si- 

 caudata, semiteres, Cucullanus elezans, Fila- 

 ria attenuata, injlexo-caudata, Spiroptera an- 

 thuris, and Stronsrylus injlexus. With Spirop- 

 tera, the two peuises are of unequal lengtli, and 

 with Aicaris paucipara, hrevinaudata,Sind Stron- 

 gylus, there is an additional horny piece like a 

 third penis. 



With most Nematodes, the penises are sulcated, 

 and those of Stronsylus have a singular form due 

 to the presence of numerous appendages. The two 

 delicate, retractor muscles of this organ, arise from 

 the internal surface of the cavity of the body, and 

 when the penis is double there are two pairs. 



Vi'ith Ascaris osculata, lestcularis, and spicu- 

 lisera, I have found these four muscles very long. 

 See upon the penis of the Nematodes, Mayer, 

 Beitr. Taf. I., and Dujardin, Hist. d. llehn. PI. 

 I.-VI. 



8 For the spermatic particles of the Nematodes, 

 see Basge, Dissert, de Strongylo, &c., p. 12, 

 fig. 27, '2ri. The development of these csU-Uke 

 spermatic particles may be easily observed with 

 Ascaris paucipara, where the parent-cells are 

 very large. In the posterior end of the testicle the 



nuclei with their nucleoli are first finned ; after- 

 wards these nuclei are siurounded by a finely- 

 granular substance around which the cell-mem- 

 brane is formed. 



In this state the testicle exactly resembles an 

 ovary tilled with eerminative vesicles and eggs. 

 Still later, the parent-cell membrane increases more 

 and more, and the granular substaucj is found 

 only upon the internal surface of the cell. Curing 

 these changes, the nucleus which resembles a ger- 

 minative vesicle, is transformed inta a long, solid, 

 and neatly-circumscribed corpuscle. With Stron- 

 gvlus auricularis, the spermatozoal [laughter .') 

 cells are pyriform ; and with Oxyuris ambigua 

 their f jrm is similar {KiiUiker, Ijc. cit. p. 73, Taf. 

 VII. fig. 26). 



It is very probable that Mayer''s assertion (Nene 

 Untersuch. aus dem Gebiete der Anat. u. Physiol. 

 1842, p. 9) that he had seen thread-like spermatic 

 particles with Oxyuris vermicularis, has led 

 KiiUiker to regard these pyriform calls as so many 

 bundles of filamentoid spermatic particles. But 

 never have I seen filaments of this kind in the Ne- 

 matodes. 



The pyriform spermatic particles of Strongylus 

 auricularis, which have a short jieduncle, as well 

 as the round, cell-like, and nucleated ones of As- 

 caris acuminata, have been figured by Reichert 

 (Beitr. zur Entwickel. der Saamenkjrp. bei deu 

 Nematoden). This same naturalist hiis shown that 

 these spermatic particles arise by endogenous gen- ' 

 eration, by fours in each cell ; see Muller's Arch. 

 1847, p. 88, Taf. VI.* 



9 The large caudal valve of the male Strongylus, 

 and the spiral tail of the male Spiroptera, may be 

 here instanced. With very many male Ascaris, 

 there are two rows of papillae upon the sides of (he 

 genital opening, and with Ascaris vesicularis, 

 and injlexa, I have found a copulatory sucker 

 directly in front of this opening. The male of 

 Hedruris androphora winds liimself about the 

 female during copulation, and the caudal valve of 

 the male Strongylus trachealis glues itself so 



* [ § 117, note 8.] The statement here made that 

 Reichert has observed the development of the 

 spei-matic particles of an Ascaris by fours in each 

 cell, deserves attention from it3 histological relation. 

 According to my own obssiTations.the histological 

 formative conditions of the development of the 

 spermatic particle are exactly analogous to those 

 of the development of the embi-yo. The nucleus 

 of the sperm-sell divides or segments like the vitel- 

 lus of the o\'um, and this process continues until 

 the sperm-cell which has now attained a large size, 

 is filled with numerous small nucleated cells 

 (daughter-cells) ; and the nucleus of these last is 

 changed into the spermatic particle. 



I think, therefore, that, invariably, the spermatic 

 particle is only a metamorphosed nucleus of a 



daughter-cell (see my Memoir, The Origin, De- 

 velopment, and Nature of the Spermatic Particles 

 in the four classes of Vertebrata, in the Mem. 

 Amer. Acad, of Arts and Sc. V. 1S53). The view 

 of fieicAeri, therefore, that four spermatic parti- 

 cles are here formed in one cell, does not ai>pear to 

 me admissible, although I have no observations 

 upon the instance in question. It appears to me 

 explicable in this way : the nucleus of the parent 

 sperm-cell underwent here only a second segment- 

 ation, thereby only four daughter-cells being pro- 

 duced. The nucleus of each of these became a 

 spermatic particle, and these four particles passed 

 into the cavity of the parent-cell. Reichert there- 

 fore, probably saw four spermatic particles in a 

 Iiarent and not in a daughter cell. — Ed. ' 



