1887.] KATURAL SCIENCES OF PHILADELPHIA. 231 



diameter of which is much greater than that of the included gem- 

 mule. 



Skeleton spicules slender, cylindrical, gradually or more abruptly 

 pointed, smooth. (PI. X, fig. iii and iv, a.a.a.) 



Dermal spicules, minute birotulates with slender, cylindrical 

 shafts, and cap-like rotules, notched at margin into five or six hooks. 

 (PI, X, as above, c.d.e.) 



Birotulates surrounding the gemmules long, but variable in length. 

 Shafts smooth, slender, particularly near the middle ; widening and 

 becoming almost club-shaped at the extremities, where the rotules 

 are formed of five or six stout, recurved, acuminate hooks. 



Meas. Diameter of gemmules 0*027 inches. Skeleton spicules 

 0-0082 by 0-0002 inches. Gemmule birotulates 0-0025 by O'OOOl 

 inches. Diameter of rotule 0-0008 inches. Length of minute dermal 

 birotulate 0-00063 inches. 



Sab. On submerged grass, weeds etc. in shallow water. 



Loc. Gilder Pond, Mt. Everett, Berkshire Co. Mass; collected 

 by F. Wolle and H. S. Kitchel: MacKay's Lake, Pictou Co. 

 Nova Scotia; Collected by A. H. MacKay. 



My friends Dr. Francis Wolle and H. S. Kitchel Esq. of Bethle- 

 hem, Pennsylvania, in the pursuit of their favorite study of des- 

 mids and diatoms visited Mt. Everett near the extreme S.W. 

 corner of Massachussetts, in September 1882. While devoted to 

 their own specialty they yet in the spirit of true naturalists found 

 real pleasui-e in gathering subjects in other departments of natural 

 history, for the benefit of their absent friends. 



In a note transmitting specimens and written immediately after 

 their return, Mr. Kitchel says. — "Gilder Pond is a small pond 

 some 1800 ft. above the sea, on the side of the mountain, fed by 

 springs at the bottom and the drainage from still higher ground ; 

 no inlet, and no outlet except a small stream, which drains through 

 the ground at one end." "It is almost entirely surrounded by rocks 

 and the water is very pure and cold." "The sj)onge was first found 

 upon the ground in shallow water; afterward in great quantities 

 on submerged bushes etc. along the edge of the jDond." 



A card from Dr. Wolle a few days later gave the elevation as 

 2400 feet. The rough sketches prepared by both gentlemen to 

 suggest its appearance while growing, indicated a delicate branching 

 sponge, but the specimens sent had been packed between cards and 

 forwarded by letter ; in one case, at least, after partial decomposition 



