58 



THE AMERICAN MONTHLY 



[Feb. 



perfect, a branch of one of the arms having been broken 

 off. It is a question also whether the branches are 

 armed with terminal spines, for two of the branches 

 lack them, and while the third shows it in the drawing, 

 in the original the end of the branch is covered by an- 

 other radiolarian form which makes it difficult to decide 

 whether what is seen is a spine on the end of the branch 



or a portion of the interior skeleton of the form which 

 obscures it. Of all the species known this has the widest 

 and by far the deepest fission of the two opposite arms. 

 The finder of this form, who has thus added not only a 

 new species to the genus but a new genus to the list of 

 'the genera from Barbabos, was Dr. 0. H. Hubbard of 

 Walpole, Mass. 



Radiolaria ; a new Species from Barbados. 



HARRY J. SUTTON, 

 PHII,AI>SI,PHIA, PA. 



Pentinastrum irregulare, n. sp. 



Arms unequal ; two slightly longer than the others, 

 twice as long as broad, at their base two-fifths as broad 

 as at their rounded distal end, which bears a terminal 

 spine. 



The diameter of the central disk is less than half the 

 length of the arms. The angles between the arms are 



