436 



SCIENCE. 



[N. S. Vol. V. No. 115. 



On the Early Development of Chimcera. Bash- 



FOED Dean. 



Emphasis was laid on tlie similarity of 

 the embryonic characters of Chimeroid and 

 Elasmobranch. 



Amphiuma and the Cmcilians. J. S. Kings- 

 ley. 



The various statements which had been 

 advanced to show the relationships of Am- 

 phiuma and Ccecilians were considered, 

 and it was pointed out that these state- 

 ments were almost entirely based upon mis- 

 interpretation or misconception. The dif- 

 ferences between the two were then empha- 

 sized, and it was shown that the structural 

 features were opposed to the view of Cope 

 that the Csecilians had descended from an 

 Amphiuma-like form, and to that of the 

 Sarasins that Amphiuma was a neoteric 

 Csecilian. In the possession of an ethmoid, 

 in structure of vertebrae, in the relations of 

 palatine and trigeminal nerves, in structure 

 of nephridia and genitalia and in circula- 

 tory apparatus, the Csecilians differ from 

 Amphiuma and from all Urodeles, and the 

 group must be regarded as entirely distinct 

 from Urodeles, and as having descended 

 directly from some Stegocephalan ancestor. 



Vertebral Intercalation in Nectun 

 by title.) H. C. Bumpus. 



(Read 



Brachial and Liimbo-sacral Plexi in Necturus. 



F. C. Waite. 



In Necturus macidosits the normal posi- 

 tion of the pelvic girdle is with attachment 

 to the 19th vertebra, but in about one- 

 fourth the cases it is attached to the 20th 

 vertebra. Unfrequent cases are found in 

 which the attachment is asymmetrical, the 

 sacral rib on one side being one segment 

 anterior to that on the other side. 



Study of the plexi in a series of speci- 

 mens shows: (a) that the position of the 

 brachial plexus does not vary with dis- 

 placement of pelvic girdle, and so it is im- 



probable that intercalation of vertebrae 

 occurs anterior to the posterior spinal 

 nerve (V) involved in this plexus ; (6) 

 with normal position of pelvic girdle there 

 are two prevalent types of topography of 

 the lumbo-sacral plexus which depend upon 

 the manner of branching of the spinal 

 nerves to form the crural nerve, and further 

 that there is considerable variation in the 

 strength of the nerves involved, causing a 

 shifting within narrow limits of the ' source 

 center ' of the plexus, (c) "When the girdle is 

 attached to 20th vertebra the plexus shows 

 a displacement posteriorly, but not in a 

 corresponding degree through an entire 

 segment. It thus occupies a position in- 

 termediate between the normal position and 

 what would be its position were it displaced 

 through an entire segment, (d) Where the 

 girdle is attached asymmetrically the plexus 

 does not show corresponding asymmetry, 

 but is essentially symmetrical in one of the 

 two segments involved. 



The intermediate position of the plexus, 

 the occurrence of symmetrical variation 

 in position of girdle ; of asymmetrically 

 placed girdles and of supernumerary sacral 

 ribs, appears to be explicable not upon 

 ground of intercalation of vertebra nor of 

 slipping of girdle during ontogeny, but upon 

 the hypothesis that there are several seg- 

 ments in this region, in any one of which a 

 girdle may be developed. 



Discovery of a Huge Octopus on the Coast of 

 Florida. A. E. Veerill. 



The following officers were elected : 

 President, C. S. Minot, Harvard; Vice- 

 President, S. I. Smith, Yale ; Secretary- 

 Treasurer, G. H. Parker, Harvard ; Mem- 

 bers of the Executive Committee from the 

 Society at large, J. S. Kingsley, Tufts, and 

 Bashford Dean, Columbia. 



G. H. Paekee, 

 Haevaed Univbe^ity. Secretary. 



