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ZOOLOGY: KOFOID AND SWEZY 
eleven species of seven genera parasitic in vertebrates. The conclusions 
are based on hundreds of preparations made by the wet Schaudinn iron- 
haematoxyhn, or by the Giemsa method, and controlled by observations 
on living forms in sealed culture sKdes, or on mixed pure cultures in 
sterilized media. 
The vegetative phase of Trichomonas augusta (fig. 1) presents an 
elongated pyriform body with a hyaline axial rod, the axostyle (ax.), 
enlarged anteriorly and projecting posteriorly in a sharp point. A pale 
spheroidal nucleus (n.) lies in the anterior end. It contains one or 
more deeply staining karyosomes and a faint chromatin network. 
The spheroidal deeply staining blepharoplast (bl., figs. 1-3) lies close 
to the anterior surface attached to the anterior end of the axostyle. 
From it pass anteriorly the three long lightly staining anterior flagella 
{ant. fl.), and posteriorly the undulating membrane {und. m.) consisting 
of a waving protoplasmic film in whose margin lies a deeply staining 
chromatic thread or margin {chr. m.), and at whose base is a heavier 
basal chromatic rod (bas. chr. r.). Posteriorly the two chromatic struc- 
tures unite at the point of emergence in the lightly staining posterior 
flagellum (post.fl.). 
From the blepharoplast the axostyle (ax.), a large hyaline club-shaped 
flexible and mobile structure, passes posteriorly in an axial position. It 
is enlarged anteriorly near the nucleus and contains a varying number 
of fairly uniform axostylar chromidia (ax. chr.). In macerated speci- 
mens (fig. 9) the nucleus is seen to be attached to the head of the axo- 
style by a persistent and but slightly chromatic strand or rhizoplast 
(rh.). These extra-nuclear structures together with the nucleus survive 
as a coherent unit the maceration of the surrounding cytoplasm. 
The prophase of the process of mitosis is initiated in rather large, 
somewhat spheroidal individuals (fig. 2), by the apparent splitting of 
the wavy chromatic margin of the undulating membrane distally from 
the blepharoplast. At the same time the homogeneous intra-nuclear 
chromidial cloud, which diffusely fills the nucleus as mitosis approaches, 
emerges from it and forms the extra-nuclear cloud (ex. chr. cL), a diffusely 
staining halo about the nucleus, in which minute chromidia soon appear 
(fig. 2) , spread into the surrounding cytoplasm, and increase in the axo- 
style throughout its length. 
As the nucleus clears up there emerges in it a distinct (fig. 2), often 
clearly continuous chromatin skein, which speedily breaks up, finally 
into five chromatin masses, or chromosomes, each of which splits longi- 
tudinally into two chromosomes (fig. 3) within the intact nuclear mem- 
brane, prior to any arrangement in an equatorial plate. There are 
