258 THE AMERICAN MONTHLY [Sept. 



isli, aromatic taste, very much like that of the violet. 

 The diatom Asterionella also produces a sweetish, aro- 

 matic taste and odor resembling that of a rose geranium, 

 although at times the Asterionella odor is decidedly 

 fishy and oily. Uroglena volvox has a strong oily taste, 

 very much like cod-liver oil. Synura uvella has, at 

 times, a somewhat oily taste, often resembling that of a 

 cucumber, but generally more spicy and bitter. The 

 taste is a very persistent one. " It stays in the mouth." 

 It is strongest at the base of the tongue, where the 

 nerves are most sensitive to bitter substances. The 

 taste of Dinobryon is similar to that of Synura, but is 

 not as strong. In all of the above mentioned organisms 

 oil-globules have been observed. In some of them the 

 amount of oil has been estimated, and in at least one of 

 them, Uroglena americana,* the oil has been isolated. It 

 remains to be determined if there is any connection be- 

 tween the presence of the pigment bands and the amount 

 of oil production. 



It should be stated that these organisms do not always 

 contain oil-globules. In the younger forms they are 

 frequently absent. The oil may be said to be a reserve 

 product, produced by the organism during its growth, 

 and stored up in the cell, — hence it is most common in 

 the older specimens. It is by the disintegration of the 

 cells and the consequent liberation of the oil that the 

 tastes are brought about. 



" The Synura animalcules are free-swimming, united 

 in sub-spherical, elongated, social clusters, each zooid 

 contained in a separate membranous sheath or lorica, 

 the posterior extremities of which are confluent. The 

 contained animalcules almost entirely fill the cavities of 

 the loricffi, their posterior extremities being produced 

 towards and adherent to the bottom of the sam.e The 



* See "Odors in Drinking Water" by Gary N. Calkins in '24tb Ann, Kep. 

 Mass. State Board of Health, 1892. 



