346 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



Tullberg's method of killing and hardening anemones for 

 macro-sectioning, as recommended by Parker, 1897, gave 

 satisfactory results. Magnesium sulphate in strong solution 

 was added to the water containing the animals until the}' 

 were thoroughly narcotized. They were then placed in a 

 one per cent, solution of chromic acid for several hours. 

 Serial sections were usually taken with a razor, a method 

 which showed satisfactorily, among all but the smallest 

 specimens, the arrangement and behavior of the mesen- 

 teries, mesenterial muscles, and siphonoglyphs. The small- 

 est specimens were sectioned on the microtome. 



In the latter part of September, 1897, a large specimen 

 of Mctridium fimbriatum was brought to the laboratory. 

 Upon expansion it was found to have divided partially into 

 three individuals. There were two complete circlets of 

 tentacles, one of which enclosed two mouths, the other but 

 one. The oral disks had but just separated. No trace of 

 division existed beyond the parapet. 



More monogenous polyps were found in small numbers 

 in the months of October, November, January to June 

 inclusive. At present I am unable to say whether they are 

 in greater abundance during some seasons than others. 

 Among 1971 polyps collected at random in May and June, 

 48 (2.43 per cent.) were monogenous. The diameter of 

 the column when well expanded varied from 2 to 30 mm 

 Sexual elements may be present. 



Three modes of monogenesis have been observed: — 



1. Longitudinal fission. 



a. Equal. 



b. Unequal. 



Oral-aboral. 

 Aboral-oral. 



2. Basal fragmentation. 



3. Budding. 



a. Pedal. 



b. (Esophageal. 



No case of transverse fission (Agassiz 1865) has as yet 

 come under my notice. 



