478 ANNALS NEW YORK ACADEMY OF SCIENCES 



The writer has had opportunity to see much of these rocks and their 

 field relations during the past three years. It seems certain that they repre- 

 sent a case of magmatic differentiation that includes not only the Cortlandt 

 series, as outlined by Dana and Williams, but two or three occurrences of 

 typical granite as well. The granite area borders the basic varieties on the 

 northeast side. Actual contacts of the larger masses are not to be seen, but 

 an occasional dike of granite cuts the adjacent diorite and gabbros, indicating 

 a relationship as one of the latest developments. Furthermore, the granite 

 shows its consanguinity by its heavy soda content, soda-lime feldspar 

 predominating. It is, however, a very acid granite and introduces a con- 

 siderably greater range of rock variety, becoming the acid extreme of the 

 Cortlandt series. 



Mr. Hyde said in abstract: The genus Camwophorella has heretofore 

 been known only by a single species from the Kinderhook at Burlington, 

 Iowa, and has always been referred to the family Pentameridse, order 

 Protremata, in which only the simplest type of brachial support is known. 

 Recently obtained material of a second species from Sciotoville, Ohio, 

 transfers it to the sub-family Meristellinae, in the order Telotremata. This 

 material is of unusual interest in that it throws a new light on the method of 

 development of the jugum in certain Athyroid types. It has been supposed 

 that this portion of the brachidium was formed in the phylogeny of the 

 group by the growth of two jugal processes, one on the basal whorl of each 

 cone, and that these united into the shape of an inverted V or U, from the 

 apex of which a short stem was continued which in time bifurcated, the 

 arms then lengthening and reuniting with the base of the stem. The 

 material referred to shows certainly that, in this form at least, the inverted 

 V or U was formed and that the remainder of the structure was laid down, 

 probably in a single plate on the surface of the U and not by any such process 

 as outlined above. 



Professor Jaggar said in abstract: The island consists of four prominent 

 peaks, old Bogoslof at the south, McCulloch Peak steaming actively in the 

 middle, Metcalf Cone (sometimes called Perry Peak) adjacent to McCulloch 

 in the north and New Bogoslof or Fire Island ("Grewingk"), a flat table 

 rock at the northwest end of the group. These are now all connected by 

 continuous gravel and sand strips, where in one place there was a broad 

 channel and seven fathoms of water a year ago. 



McCulloch Peak and Metcalf Cone are both products of the slow push- 

 ing up from beneath the waves of a mass of refractory lava, semi-solid, 

 crusting and breaking into blocks as it rises, with only the central portions 

 retaining a semblance of fluidity. 



In 1796 Old Bogoslof rose. In 1884 New Bogoslof, Fire Island, came 



