ZOOLOaY AND BOTANY, MICROSCOPY, ETC, 233 



then dissected out with needles as carefully as possible, and a drop 

 or two of hgematoxylin poured on to the slide. When the retina had 

 been standing in hsematoxylin in this manner for some hours it was 

 washed with water, teased out with fine needles, and mounted in 

 glycerine. 



MoUuscoida. 



Segmental Organs of the Endoproct Bryozoa.*— M. L. Joliet, after 

 pointing out the causes which so frequently obscure the detection of 

 this organ in PedicelUna, describes it as a short stylet, which seems to 

 arise from the point at which the " matrix " abuts on the crown of 

 tentacles, and to pass obliquely downwards towards the cesophagus. 

 Along this stylet it is quite easy to see the ciliary movement, which 

 gives a wheel-like movement to the terminal enlargement ; on altering 

 the focus, a similar stylet may be observed on the other side of 

 the oesophagus. When examined with a higher power (No. 9 Hart- 

 nack, in place of No. 4), the stylet is seen to be a canal, slightly 

 swollen in its middle, with its axial cavity having the appearance of a 

 blackish line, which is fine at some points and thickened at others ; 

 as to the relations of this canal with the exterior, the terminal 

 enlargement is infundibular in form, and its free edge is thickened 

 into a welt, and prolonged into a delicate lip. The internal surface 

 of the canal is covered with vibratile cilia, which work from within 

 outwards, and round the spiral enlargement near the free extremity 

 of the canal. 



Characters which speak to the two organs being homologous are 

 to be found in the segmental organ of Loxosoma ; for the present 

 it seems to be well not to speak definitely of a similar structure 

 in any other Bryozoon. What bearing have the facts adduced on the 

 affinities of these animals ? The relations between them and the Bra- 

 chiopoda, to which Professor Huxley and others have already directed 

 attention, seemed to be aided by the observations now recorded ; 

 in illustration of this point M. Joliet gives a useful diagram. 



As is well known, the organs which Hancock and Lacaze-Duthiers 

 have shown to be renal organs were formerly regarded as hearts. 

 Translating Professor Huxley, the writer quotes these words : " If we 

 shall succeed in showing that the so-called hearts are not really such, 

 ' ce sera une dissemblance de moins.' " Speaking for himself, Joliet 

 says : " I hope I have shown that they are the hoinologues of organs 

 which are also found in the Bryozoa, and at the same point : ' ce sera 

 une ressemhlance de "plus.' " 



EelationsMp of the Genus Heteropora to Monticulipora.f — Pro- 

 fessor H. AUeyne Nicholson, in an important paper, undertakes a 

 comparative examination of a recent Heteropora, with the object of 

 determining if Monticulipora should be removed to the Bryozoa. For 

 the purpose he made elaborate examinations of pieces of Heteropora 

 in his possession (with specimens of which he had previously fur- 

 nished Mr. Busk), which were named H. neozelanica Busk, but 



* Arch. Zool. Exp. et Gen. viii. (1880) pp. 497-512. 



t Ann. and Mag. Nat. Hist., vi. (1880) pp. 329-39, 414-23. 



