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this segment. The author believed that the genital ducts of the female were 

 homologous with the viscero-pericardial pores , and that they, together with 

 the anterior pair of renal sacs , represented the nephridia of the genital seg- 

 ment. The extremely archaic character of the ovary was described as well as 

 the origin of the ova from syncytial masses of protoplasm. He also attempted 

 to show that the penis was a paired structure, developed from the outer skin, 

 one moiety remaining rudimentary , and having lost its communication with 

 the true genital duct (here the pyriform sac). Certain points in the arrange- 

 ment of the nervous system were touched upon , and it was suggested that 

 a continuation backward on each side of the nerve-trunk , the branches of 

 which innervated the gills, to the region of the post-anal papilla represented 

 the supra-anal commissure of the Amphineura. The curious laminated or- 

 gan ventral to the buccal mass in the female, which had been believed to be 

 olfactory , was pointed out as probably having some connection with repro- 

 duction — apparently being a glandular apparatus to which the spermato- 

 phore of the male became attached. The question of the morphological 

 meaning of the arms in Cephalopods was discussed briefly. It was pointed 

 out that the only strong basis on which the hypothesis of the pedal nature 

 of these organs rested was that derived from the consideration of their in- 

 nervation by the »pedal« ganglion or a derivative of it. And the force of 

 this evidence was completely dependent upon the assumption that this gan- 

 glion was precisely homologous with the pedal ganglia of Gasteropods ; and 

 this assumption appeared to be unjustified, the evidence of comparative ana- 

 tomy pointing to the independent phylogenetic development of the several 

 ganglia of Gasteropods , and of the similarly named ganglia in the higher 

 Cephalopods, from a condition of continuous nerve-strands such as occurred 

 in Chiton^ Nautilus, and other archaic forms. The author advocated the ab- 

 andonment of the view that the arms are pedal, and the resumption of what 

 appeared the inherently more probable view , that they are processes of the 

 head-region. In conclusion, the author drew attention to certain indications 

 which appeared to point to the Amphineura, and especially to the Chitons, 

 as being of all living Mollusca those which most nearly approximate to the 

 ancestral form of the time when the Cephalopods diverged from the main 

 Molluscan stem. — A communication was read from Mr. F. E. Bed dard, 

 F.R.S., and Mr. A. C. Haddon, containing an account of a collection of 

 Nudibranchiate Mollusca recently made by the latter in Torres Straits. — 

 Mr. Boulenger read a paper on a large collection of fishes made by Dr. C. 

 Ternitz in the Rio Paraguay. Among the new species were : — Plagioscion 

 Ternitzii (allied to P. surinamensis , Blkr., with the formula D. X, I 33 — 35. 

 So. 95 — 100 ^' ~ ; 1. 1. 48 — 50), Geojihagus duodecimsjnnosus (D. XII 14. 

 A. Ill 9, Sc. 30 j^; 1. 1. j-) , Oxydoras Eigenmanni , connecting Oxydoras 

 and Rhmodoras (agreeing with the former in the serrature of the dorsal spine, 

 with the latter in all other respects), Chaetostomus gigas (closely allied to Ch. 

 acideatus , but with the belly studded with rough shields) , and Anacyrtus 

 prognathus (characterized by a strongly projecting, squarely truncated snout). 

 — A communication was read from the Babu Ram Bramha S any al, 

 C.M.Z.S., giving an account of the moulting of some Birds of Paradise in 

 the Zoological Gardens , Calcutta. — A communication was read from Mr. 

 O. Thomas and Col. J. W. Yerbury, giving a description of a collection 

 of Mammals made at Aden by Col. Yerbury in the winter of this year. It 



