488 DESCRIPTION or {Polygastrica. 



other substances in sea-water. In the gelatinous cells, Ehrenberg 

 observed from one to twenty navicular corpuscles. 



Pkusttilta salina. — Transversely striated, very narrowly linear, 

 straight, suddenly acute at each end in one aspect, but in another 

 rounded ; densely distributed within the gelatinous investment. 

 Length l-2300th to l-860th. In saline springs, Germany. 



Genus Gloeonema (Ehr.) — Has a double envelope, the inner one, 

 or true lorica, curved and siliceous ; outer one combustible, tubular, 

 often branched, and containing many individuals. The enclosed 

 bodies multiply by self- division, and in habit approach Navicula, or 

 more nearly Cocconema. 



This genus is not admitted by Kiitzing, who charges Ehrenberg 

 with producing confusion, both by staling the Encyonema fwradoxum 

 of his synopsis to be synonymous with Oloeonema paradoxum (Agardh), 

 and by describing it under this name, when, indeed, the species so- 

 called by Agardh was not a member of the family Biatomece (see 

 Encyonema.) This so-called Oloeonema of Agardh, indeed, has been 

 determined by Mr. Berkeley to be nothing less than the eggs of an 

 insect, with a common connecting mucous investment of a tubular 

 form. 



G. (?) triangulum. — Corpuscles navicular, unequal, dorsum 

 gibbous, approaching a triangular form laterally. Diameter 1- 782nd. 

 Alive at Niagara. "I have not met with continuous tubules, but have 

 seen it associated with G. paradoxum, the tubules of which were 

 present along with scattered corpuscles of a similar character." Bailey. 



G. sigmoides. — Corpuscles oblong, linear, flexuose, sigmoid, acute, 

 striated, enclosed in gelatinous, simple tubules, in single rows. 

 Length 1-1 300th. Living in Demerara. 



G. sinense. — Corpuscles oblong, striated ; apices abruptly reflexed 

 after the manner of tnany Eunofia. Length l-576th. 



G. paradoxum = Encyonema faradoxum (Kiitz.) — Semi-ovate, 

 curved, striated, inclosed in hyaline, simple or rarely branched tubes. 

 Ehrenberg remarks, " I found this species very abundantly amongst 

 Mytilus polymorphus, upon Conferva rivularis, and saw both simple 

 and branched threads ; the little bodies, or corpuscles, being seldom 

 arranged in two rows, but mostly in one. It is a very remarkable 

 circumstance that I very often foimd two different sorts of these 



