Smithsonian miscellaneous collections . uth; Opl, operculum; Pdp, pedipalp; SpS, sperm sac:TCnl, testicular canal: vO, ventral ocellus. The male gonads of XipJiosnra polyphenms, as described by Benham(1883), consist of an intricate network of branching and reunitingtesticular canals (fig. 8 B, C, TCnl) spread through the entire upperpart of the body. The spermatocytes are developed in numeroussmall follicular diverticula, or sperm sacs {SpS), opening from thecanals, and the mature spermatozoa are discharged through a pairof short vasa deferentia (fig. 9 B, Vd), which open separately on thegeni
Smithsonian miscellaneous collections . uth; Opl, operculum; Pdp, pedipalp; SpS, sperm sac:TCnl, testicular canal: vO, ventral ocellus. The male gonads of XipJiosnra polyphenms, as described by Benham(1883), consist of an intricate network of branching and reunitingtesticular canals (fig. 8 B, C, TCnl) spread through the entire upperpart of the body. The spermatocytes are developed in numeroussmall follicular diverticula, or sperm sacs {SpS), opening from thecanals, and the mature spermatozoa are discharged through a pairof short vasa deferentia (fig. 9 B, Vd), which open separately on thegenital papillae situated on the posterior (dorsal) surface of the base xo. 14 INSECT A M K N— SNODGRASS 27 of the operculum {Fai). The origans of the female are essentiallylike those of the male, and open on a pair of similar papillae. The oi)erculum (fig. 9 A, 1)) clearly includes in its compositiona ])air of appendages similar to the following gill—bearing appendages( C. D), but the median membranous area of its base (B, V), on. ill-bearing appendages of Xipho- FiG. 9.—Xiphosurida: operculum and firstsura Polyphemus, male. A, anterior (under) surface of operculum. B, posterior (upper) surface ofoperculum, with penes on median membranous area of base. C, first opistho-somal appendages, anterior (under) surface. D, posterior (upper) surface ofright first opisthosomal appendage and median membrane. a-1, subdivisions and sutures of appendages (see text); Brn, branchiae; ;;;.median tongue of venter; Pen, penis; V, membranous venter of segment of appendages; Id, vas deferens. which are situated the genital papillae, appears to be a fold of theventer of the opercular segment intercalated between the lateral appen-dicular elements. In the following segments the median membraneentirely separates the appendages (C, D, V) and ends with a freedistal process (D, m) between them. The genital openmgs of theXiphosurida, therefore, are situated, not on the bases of the a
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Keywords: ., bookcentury1800, bookdecade1860, bookidsmiths, booksubjectscience
