OCR Text |
Show 222 MR. F. E. BEDDARD ON NEW EARTHWORMS. [Mar. 19, (11) Acanthodrilus corralensis, n. sp. Of this species there was only a single individual. It is tolerably large, measuring 103 m m . in length by 5 m m . in diameter ; number of segments 145. The colour is very much that of Acanthodrilus pictus; and it also resembles that species in the fact that the prostomium only extends over about one half of the buccal segment. On the other hand, Acanthodrilus corralensis differs from A. pictus in that the setae are strictly paired from end to end of the body, being only to a very slight extent separated at the posterior end of the body. In this region the body has a roughly quadrangular section, the setae being implanted at the angles. The symmetry of the figure, however, is broken, owing to the two ventral pairs being closer together than the two dorsal. The clitellum occupies segments xiii.-xvii. and is complete. The dorsal pores commence at any rate in the clitellar region. None of the intersegmental septa are especially thick. Those separating segments x./xiii. are rather stouter than the others. The gizzard lies anteriorly to the first pair of spermathecae, but I am not able to fix its segment with precision. In the xivth and xvth segments, particularly in the latter, the oesophagus is enlarged and highly vascular, its lining membrane being folded. The last pair of hearts are in segment xii. The testes and sperm-duct funnels are one pair only in segment x. The racemose sperm-sacs are in ix. and xi. The spermiducal glands are like those of a few other species of the genus in that the anterior pair are distinctly larger than the posterior. The penial setae, of which there were two in the bundle that I examined (the posterior on the left side), are crooked at the end like a crosier. The ends of the setae have numerous denticulate ridges. The setae resemble, in fact, very closely the penial setae of A. pictus. The spermathecae are not very large; each is an oval sac, to the duct of which is fixed the very slender duct of the appendix, widening out above into an oval sac. The diverticulum of the spermatheca is about half the size of tbe pouch. Hab. St. 47, Corral, " Wald, unter Steinen."' (12) Acanthodrilus simulans, n. sp. This species was found in a large gathering of worms from Corral in company with the last species and with a considerable number of examples of Microscolex spatulifer. The external characters of A. simulans are so like those of the last-named species that they were at first passed over accidentally. It is the colour which is so strikingly like. In the specimens of M. spatulifer from this locality the colour of the dorsal surface was a reddish brown instead of the more usual violet. Precisely the same colour was found in the Acanthodrilus. As this species is also |