May 10, 1907] 



SCIENCE 



733 



ho-wever, while the anterior part is con- 

 stricted as figured by Girard for the New- 

 port specimens. It is evident that two 

 and possibly three species were confused by 

 Leidy under the one name. Bis material 

 was given to Girard and thus far it has 

 been impossible to locate it. 



The second form occurring at Gambler is 

 considerably smaller than the preceding 

 one as well as much lighter in color. Only 

 two examples have been found, both under 

 stones in damp woods. It seems quite 

 distinct from any of those taken by Leidy 

 as well as the species tabulated by von 

 Graff in his excellent monograph. 



Some papers in preparation dealing with 

 the anatomical structure of the forms will 

 probably make clear their systematic posi- 

 tion. Furthermore, it appears evident 

 that land planarians are widely distributed 

 over the United States and that by reason 

 of their similarity to young snails, they 

 have often been overlooked by collectors. 



Some Little-hnown Shark Brains, with 

 Suggestions as to Methods: Bukt G. 

 WiLDEE, Cornell University. 

 This paper continues that of which an 

 abstract was printed in Science for May 

 26, 1905. Now first, so far as I know, are 

 shown the brains of Heterodontus {Cestra- 

 cion) and Pristiophorus. With the former 

 the cerebrum and cerebellum resemble 

 those of the 'acanth' {Squalus acanthias), 

 indicating an antiquity little if any 

 greater. Notwithstanding certain ectal re- 

 semblances of the two dentirostral genera, 

 Pristis, the 'saw-ray' and Pristiophorus, 

 the 'saw-shark,' their brains differ mark- 

 edly, the latter 's being the more primitive. 

 Their inclusion within the same family or 

 even the same division would seem to me 

 an error less only in degree than would 

 be their combination with Xiphias, Polyo- 

 don and Psephunis as 'Rostrata,' or than 

 was Glinther's association of Ganoids and 



Selachians as 'Palseichthyes,' aptly char- 

 acterized by Gill as a 'piece of scientific 

 gaucherie.' Upon encephalic grounds I 

 think Pristiophorus and Scymnorhinus 

 should be excluded from the Squalidae, and 

 Sphyma from the Carehariida. The brain 

 of each selachian genus is, I think, recog- 

 nizable, but I am less certain as to family 

 forms. The Notidanoid or Diplospondy- 

 lous type is well marked, and includes 

 Scymnorhinus. At present the rays can 

 not be distinguished from the sharks in any 

 such simple way as, e. g., the Anura may 

 be from the Urodela by the secondary 

 fusion of the olfactory bulbs. Perhaps, in 

 no shark is the prosocele so nearly obliter- 

 ated as it seems to be in all rays. In no 

 ray do the cerebral protrusions remain un- 

 conjoined as in some sharks; but, para- 

 doxically, in no ray is there, as in several 

 sharks, so nearly a complete obliteration of 

 the evidence of their primary independ- 

 ence. Under 'methods' may be enumer- 

 ated: (1) The need of well-preserved 

 brains of all species; (2) maintaining the 

 natural contours, especially of thinner 

 parts, by injecting the preservative into 

 the cavities; (3) making solid injections of 

 the cavities; (4) exposing brains with a 

 'shoe-knife,' obliquely shortened; (5) ex- 

 ploring with the 'syringotome' or canali- 

 culus knife; (6) the use of sheets of uni- 

 form size, say 35 x 45 cm., upon which, in 

 a manner permitting change, are drawn 

 outlines of the animal and of its character- 

 istic parts, especially the brain ; such sheets 

 may be arranged and rearranged upon the 

 wall so as to facilitate research and ex- 

 position to small classes. 



The Primary Septa in the Rugose Corals: 

 Clarence E. Goedon, Amherst Mass. 

 The number of these septa is still in 

 dispute. The assertion of Professor Duer- 

 den that there are six protosepta is con- 

 tradicted by other evidence of an important 



