CHROMIDIA AND THE BINUCLEARITY HYPOTHESES. 291 
several flagellates. Prowazek (’03) recorded the presence of 
a “chromidium” in Bicosceca. He subsequently (’04) found 
a similar body in Bodo lacerte. ‘This structure lies near 
the nucleus, but it is difficult to see why it is called a “ chro- 
midium.” Of its origin and fate nothing is known. It stains 
(in Bodo) with iron-haematoxylin but not with other chro- 
matin stains, and perhaps consists of plastin! (text-fig. 8). 
Prowazek has further described (’04) the formation of 
“chromidia”’ as a preliminary to a remarkable process of 
autogamy in Bodo. I will not discuss this further here as I 
have gone into the matter more fully elsewhere (Dobell, ’?08c). 
Suffice it to say that Prowazek probably mistook stages in 
TrxtT-Fic. 8. 
Bodo lacertex, from a preparation stained with hematoxylin 
and eosin. ‘he so-called “ chromidium” (ch.) is stained 
bright red, in striking contrast with the violet nucleus (v.). 
(Original.) 
the development of yeast-like organisms for stages in the 
life-history of Bodo. The “chromidia” are reserve material. 
At all events the existence of chromidia in this animal is 
very doubtful. 
Chromidia are said to play a part in the life-history of 
Hemoproteus (Trypanosoma) noctue, (Schaudinn, ’04, 
05). They appear to be of a metabolic nature, as in 
Actinospherium (cf. pp. 282, 283). 
There are some other cases of chromidia recorded in 
flagellates, but they are not very satisfactory. In Joenia 
! In Rhizopods the chromidial net may consist largely of plastin, and 
contain very little chromatin, so possibly this structure in Bodo is of a 
similar nature. Cf. Dofiein (07): “In Trinema conditions occur in 
which the chromidial body fills the apical part of the delicate shell as an 
almost compact, uniform mass of plastin.” 
