A Study of One of the Distomes. 85 



irregular or variable number of tubules is probably due to the 

 fact that sometimes one or more become accidently broken off. 

 If we admire the instincts of birds and bees, and wonder that 

 such low animals as tubiculous worms can construct for their 

 protection encasements of united particles of sand, how much 

 more marvelous is it that we find organisms so low as the 

 amoeba, almost structureless masses of living protoplasm, 

 endowed with this wonderful, inherited habit of constructing 

 artificial houses for themselves ! 



Another admirable exhibition of Rhizopod architecture is 

 shown in the genus Ei/glyp/ia, to which I shall add one new 

 form. 



Euglypha tegi/life?'a, nov. sp. (Plate VIII., Fig. 4). This is a 

 beautiful little Rhizopod, and is characterized by a peculiar and 

 interesting shell. It occurs among fresh-water Algae, as I have 

 seen it in New York, with an ovoid test, glistening in strong 

 light from the effect of a layer of crystalline blocks of un- 

 equal height, v/hich pave the external surface. The inner 

 homogeneous capsule upon which the pavement lies, is quite 

 thick, exhibiting the color of diatomin, and forming a smooth 

 (not dentate) margin about the pseudopodal orifice. Protected 

 within this hard, rough case lies the delicate, granular, plasmic, 

 amoeboid body, which does not entirely fill the shell, but pre- 

 sents a large nucleus and several small vacuoles, at times 

 extending itself outwards by long, usually branching, some- 

 times anastamosing, pseudopods. 



From among the great number of our fresh-water Rhizopods 

 which I have studied, and which are mostly varieties of known 

 species, only the few above mentioned are presented because 

 they are new. 



Oskaloosa College, Iowa. 



A STUDY OF ONE OF THE DISTOMES. 



BY C. H. STOWELL, M. D. 



{Received October I'jt/i, 1878.) 

 Van Beneden says : "The parasite is he whose profession 

 it is to live at the expense of his neighbor, and whose only 

 employment consists in taking advantage of him, but pru- 

 dently, so as not to endanger his life. He is a pauper who 



