1902.] NATURAL SCIEXCES OF THILADELPHIA. 507 



the oruameut alien it is more likely that F. contrarium was derived 

 from a precursor of F. perversum, of which the modern spinose form 

 of that species is the living representative. F. contrarium would, 

 according to the speaker's judgment, be a side branch, and not in 

 the direct line of ancestry. Some sinistral INIiocene Fulgurs, after 

 losing the primitive ornamentation, develop spines again on the 

 rounded adult whorl, prf)ducing a form much like the modern typi- 

 cal F. perversum. A tendency similar to this has been noted in 

 Miocene dextral shells of the non -canaliculate division F. maximum. 



The abnormal specimen of Fulgur canaliculatum exhibited was 

 found on the beach at Lougport, New Jersey, on March 18, 1902, 

 after a storm. Some accident occurrins: when the sliell was young 

 has caused it to grow so that the shoulder angle, so cliaracteristic 

 of the species, has disappeared, and we get a shell with a rounded 

 whorl nuich like Fulgur pyrum in appearance. The break in the 

 shoulder occurred on a whorl which possessed the nodes character- 

 istic of the earlier whorls of F. canaliculatum. After the break 

 there is apparently an attempt to reproduce these nodes on the 

 rounded surface of the whorl. The faint spiral ridge which occurs 

 well over to the left on the last whorl has evidently been caused by 

 another accident. On examining the soft parts of this specimen it 

 appears to be identical with the normal male specimens, except that 

 the shoulder angle is not present on the mantle. 



On examining a normal male Fulgur canaliculatum, it will be 

 seen that the backward folded penis lies directly under the shoulder 

 angle. In the abnormal specimen the penis, as Avell as the other 

 oi'gans of the mantle cavity, all seem to be intact. The absence of 

 the shoulder angle does not seem to be connected in any way with 

 the underlying reproductive organ. It is interesting to note that 

 the shoulder angle occurs equally well developed in the female of 

 F. canaliculatum, though in this case it corresponds with no under- 

 lying organ. No peculiai'ity in the mantle edge or other soft parts 

 of this abnormal specimen, accounting for the change in shell form 

 and ornamentation which has occurred, had been discovered. 



During the past winter, while searching for the young shells of 

 our recent New Jersey Fulgurs, a series of F. carica was obtained 

 which seems to exhibit sexual dimor})hism. The adult males are all 

 smaller than the adult females. IJotli males and females have about 

 6^7 whorls, and show the adult characters of the swelling on the 

 branchial siphon and the degeneracy of the spines on the last 

 whorl. 



Accounting for the Depth of the Wyoming Buried Valley. — ^Ir. 

 Bex.tamin Smith Lyman spoke on certain geological features of 

 the Wyoming valley in Pennsylvania. It has long boon matter for 

 speculation and serious practical iiK^uiry how the ancient Susque- 

 hanna valley, buried under glacial rubbish near Wyoming and 



