No. 416.] PROTOZOA OF ESPECIAL INTEREST. 653 
striking peculiarities were well established. It is assumed by 
Bütschli and by the majority of others who adopt the hypoth- 
esis that the ciliates were derived from the Mastigophora, 
that the original forms may have been similar to the present 
genus Multicilia, whose motile organs are more like flagella 
than they are like cilia. There is no close connection between 
the cilia and flagella, as there is between the latter and pseudo- 
podia, but Bütschli holds that the Ciliata might have been 
derived from such a form as Multicilia, in which the motile 
organs became progressively shortened and increased in 
number. 
There is another hypothesis which has been maintained by 
Entz and Maupas amongst others, in which the Ciliata are 
derived from the Rhizopoda through such forms as Actinobolus 
and the Enchelinidæ in general, two types of which have been 
found in Van Cortlandt water, Lacrymaria and Actinobolus. 
Before speaking of this hypothesis in detail I will add a few 
notes on these two genera. 
Lacrymaria olar Ehr. 
Of all known micro-organisms, Lacrymaria olar is the most 
remarkable for its elasticity, and manner in which it stretches 
Out a neck-like portion bearing the mouth. The wonderful 
variability of this portion of the body cannot be represented in 
a figure, but when one has witnessed the contortions which it 
undergoes he will never forget the organism. Sometimes the 
“neck” is stretched forwards in a straight line to a distance 
equal to six times the diameter of the body ; again it may be 
wound around the body of the animal from the insertion point 
to the posterior end of the animal, and forward again on the 
other side ; and even then it may stretch out to a considerable 
distance in advance of the forward end ; or, on the other hand, 
it may be retracted until the mouth appears to be merely the 
extremity of an ovoid body. 
Lacrymaria is not an uncommon form, and in the present 
Connection it is mentioned chiefly for its bearing upon the 
hypothesis as to the origin of the Suctoria. 
