192 PROCEEDINGS OF THE ACADEMY OF [1887. 



indifferent observers from remote districts, where tlieir life history 

 has never been followed; next, from the light thrown upon the 

 character of these bodies ; that they are probably neither ova nor 

 ovaria,in any proper sense; but may be (/ems or gemmules, just as, in 

 the vegetable world, we regard the buds of trees, bulbs, tubers etc ; 

 places where the vital particles of the animal or the plant retire for 

 protection during the winter season and for successful distribution 

 in the spring: farther, that this act is coincident with the dis- 

 appearance, at least partially, of the sarcode from those parts of the 

 sponge where the gemmules are found ; and that it takes place in 

 different situations and with varying species, at widely different 

 seasons of the year. 



S. lacustris, var. montana, Potts. (PI. VII, fig. vi.) Proc. Acad. Nat. Sci. Phila. 

 1880 p. 357. 



This variety was first sent to me by Prof. E. D. Cope, as collected 

 in the well known Lake near the Mountain House on Catskill Mts., 

 N. Y., at an elevation popularly stated to be 2500 feet above tide. 

 Afterward, at my request. Dr. J. G. Hunt kindly sought for and 

 found it at the same locality. As received from the latter collector 

 the sponge was bright green with slender cylindrical branches. 



Gemmules quite numerous throughout the sponge ; often naked, 

 but also frequently covered by a thick crust and an abundance of 

 spicules, that are placed in a nearly erect position, embedded in the 

 crust. 



Skeleton spicules long, very slender, cylindrical, abruptly pointed. 



Dermal spicules apparently very scarce, slender, minute acerates ; 

 entirely spined. (None are represented in the drawing.) 



Gemmule spicules slender, cylindrical ; more sparsely spined ; 

 spines erect, long, cylindrical ; terminations rounded. 



Meas. Diameter of gemmules 0.015 inches. Skeleton spicules, 

 0.0096 by 0.00015 inches. Length of dermal spicules 0.00375 ; of 

 gemmule spicules 0.002 inches. 



This sponge in all its parts is a very slender edition of iS, lacustris 

 but I think deserves a varietal designation. 



S. lacustris, var. multiforis, Carter. Ann. etc. 1881, p. 88. 



I understand Mr. Carter to agree with me in now regarding this 

 as a variety of S. lacustris; the multiple openings being probably 

 the result, in degree, of over maturity. There are no distinctive 

 features except that the skeleton spicules in the fragments sent me 

 are unusually large. 



