1883.J NATURAL SCIENCES OF PHILADELPHIA. 125 



June 5. 



The Rev, H. C. McCook, Vice-President, in the chair. 



Twenty-five persons present. 



A paper entitled " On the Genus Hyliota," by Graceanna Lewis, 

 was presented for publication. 



The death of Dr. W. Lehman Wells, a member, was announced. 



Observations on Actinosphserium eichornii. — A communication 

 from Miss S. G. Foulke on Actinosphserium eichornii was read 

 by Prof. H. Carvill Jjewis. 



It was stated that while observing Actinosphseria, four indi- 

 viduals were seen to become fused, as it were, into one mass. 



At the end of an hour, this mass had separated into three 

 Actinosphaeria, two of the original four remaining fused into one. 



This double one then became constricted, a little to one side of 

 the middle, apparentl,y being about to separate. In a few minutes 

 the Actinosphserium began to eject, at the point of constriction, 

 a thin protoplasmic substance containing transparent granulated 

 globules and free granules. By a waving motion of the rays, the 

 masses of ejected matter were broken up, and the globules set 

 free in the water. 



These globules developed from one side an extremel}^ long ray 

 of finely granular protoplasm, slightly elongating at the same 

 time, thus taking an oval shape. No trace of the axial threads 

 peculiar to the rays of adult Actinosphaeria could be discovered. 

 The average length of these globules, including the ray, was 

 •1422 mm. ; without the ray, •0121 mm. 



The next act of the globules was the sending out another ray 

 from a point opposite to the first. Minute vacuoles appeared and 

 ranged themselves close to the surface of the globule. Other 

 rays were developed at various intervals of time. The appearance 

 of the young Actinosphaeria gradually became more perfect in 

 resemblance to the parent. The growth was very slow, the perfect 

 form not being attained for a period varying from one to two 

 weeks, and tlie size was even then small. 



The external layer of vacuoles of the Actinosphserium, from 

 which the globules had been ejected, contained numbers of 

 granules in active motion. In the different vacuoles the number 

 varied from ten to about one hundred, as nearly as could be 

 counted. Tliey were usually congregated at one point and seemed 

 to be trying to force a way out. 



Sometimes a globular mass of protoplasm was seen to run 

 out upon a ray, and then, instead of returning to the body as 

 usual, drop off" into the water, and develop into a peifect Actinc- 



