| OCR Text |
Show 1895.] MR. F. E. BEDDARD ON NEW EARTHWORMS. 215 The spermiducal glands are small and narrow ; they are confined to their respective segments (the xviith and xixth), and lie transversely to the long axis of the body. The penial setae with which tbey are provided are slender and unornamented. The spermathecae are like those of many species of Perichceta in the narrow tubular appendix, which is of the same length as the pouch. The diverticulum ends in a small dilatation. Hab. St. 7, Valparaiso, Salto ; St. 12, Valparaiso, Garten. (3) Acanthodrilus magellanicus, n. sp. There were several specimens of this species, of which the one selected for measurement was 66 m m . long and 3-5 m m . in diameter; it consisted of nearly 100 segments. The colour after preservation was a yellowish grey, owing to the absence of integumental pigment. The setae are not strictly paired; the ventral setae are nearer together than the lateral setae; but in the posterior part of the body there was less difference in tbe distance between the setae. The clitellum occupies segments xiii.-xvii. On segment xi. are a pair of large genital papillae. On the middle of segments xiv. and xv. is a narrow band of glandular appearance ; finally, the pores of the spemiducal glands are situated upon large oval papillae united nearly or completely in the middle line; they also bulge over the intervening segment so as to nearly obliterate it. Corresponding to the position of the ventral setae on segments xvii. and xix. are the apertures of the spermiducal glands. When this part of the body is mounted entire in glycerine and examined, the summit of each of the four papillae already referred to is seen to be perforated by three orifices. One is the actual pore of the gland ; the two others each correspond to one of the two penial setae which accompany the glands ; it is not common for the setae to open thus independently of the glands. The orifices are precisely similar in appearance and are of equal size. This species has a well-marked gizzard in segment vi. The septa separating segments vi./xii. are stout; the first septum lies between segments v./vi. The last heart is in segment xii. The funnels of the sperm-ducts he in segments x., xi.; the racemose sperm-sacs are in xi., xii. The two pairs of spermathecae lie as usual in viii., ix.; the pouch itself is oval, and it communicates with the exterior by a long cylindrical duct, which is not very much narrower but is rather longer. Just before the external orifice of the latter are two caeca, which really open by a common pore; they lie one above the other, and not laterally and symmetrically as in Acanthodrilus bovei. The two caeca are enveloped in a common sheath, but they are divided by a constriction superficially, which marks a real muscular septum which separates the two diverticula. The lower one is globular in form; the upper, which is larger, is more elongate. |
