ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 279' 



will not do ; Verrill * has shown that the worm does not belong to the 

 genus Staurocephalus (rectius Stauronereis) Verr. ; but Yen-ill's proposal 

 of a new name Mayeria is dismissed by Ehlers, who holds that the 

 Atlantic Palolo-worm is clearly a Eunicid, and not far removed from the 

 Etinice viridis and the other Eunicid which form the Palolo of Samoa. 



Histological Observations on Annelids.f — 11. S. Bergh notes some 

 points in regard to tbe histology of the larva of Aulastoma. He now 

 finds that the primitive epidermis consists of a very few large cells 

 containing numerous minute nuclei, whereas he previously regarded 

 each of these nuclei as corresponding to a cell. Also what he previously 

 regarded as small muscle-fibrils prove to be only ridges on the epidermis. 

 He further amplifies and corrects some of his previous observations on 

 the pronephridia. By staining with silver he has also been able to make 

 out cell-boundaries in all regions of the segmental organs of various 

 Lumbricida3, even in cases where these have not hitherto been observed. 

 He has, however, not been successful in doing this with the segmental 

 organs of the Limicolse. 



Hamingia arctica4 — A. S. Skorikow has a note upon this form,, 

 which he believes to be identical with Horst's H. glacialis. Koren and 

 Danielssen included a rudimentary proboscis among the generic cha- 

 racters of their genus Hamingia, but Skorikow figures a specimen of 

 H. arctica with a well-developed proboscis bifid at the tip. He also 

 finds two uteri, not one as in Prof. Lankester's specimen. He gives 

 the relations of Bonellia, Thalassema, and Hamingia as follows. In 

 Hamingia, as in Thalassema, the body is cylindrical, the proboscis is 

 nearly as long as the body, there are two uteri (some species of Thalas- 

 sema). Again, Hamingia resembles Bonellia and differs from Thalas- 

 sema in having the proboscis bifid at the tip (though Thalassema 

 lankesteri shows an approach to this condition), and in having a branched 

 cloacal nephridium ; in both also the male is microscopic. In Hamingia 

 the genital bristles are absent, which is a peculiar character. 



North American 01igochaeta.§ — Frank Smith describes as Premno- 

 drilus palustris g. et sp. n., a new Oligocksete which appears to be 

 related to the Lumbriculid genera Eclipidrilus and Mesoporodrilus. 

 Each of these three genera includes only a single species, and they 

 have, as common characters, the presence of sperm-reservoirs, 'simple 

 setae, an evertible penis, and very extensive sperm-sacs ; they may be 

 regarded as constituting a special sub-family Eclipidrilinae. The new 

 form seems most closely related to Mesoporodrilus, and agrees with it 

 in possessing the following characters : — a prostomium, only one pair 

 of nephridia in front of the genitalia, unpaired nephridia posterior to 

 segment xii., one pair of testes, two pairs of lateral vessels in each of 

 the somites posterior to x., and no perigastric vessels ending blindly in 

 the ccelom. In spite of these resemblances, the differences seem suffi- 

 ciently marked to entitle the new form to generic rank, but this cannot, 

 be regarded as certain until more specimens have been studied. 



* Trans. Connecticut Acad., x. (1900). 

 t Zeitsckr. wiss. Zool.. lxvi. (1901) pp. 444-56 (2 pis.). 

 J Zool. Anzeig., xsiv. (3901) pp. 158-60 (1 fig.). 

 § Bull. Illinois State Lab. Nat. Hist., v. (1900) pp. 459-78 (1 pi.). 



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