28 
F. Cavers. 
as to whether or not there is a continuous spireme in Lilium, though 
it was believed that such was formed later on (and as I now think 
erroneously), it is remarked, “ perhaps the matter is not of very 
great importance.” .... (Farmer and Moore, 1905, loc. cit., p. 508). 
The belief in a continuous spireme, so prevalent at that time, 
was, as a matter of fact, one of the serious theoretical difficulties 
we had to encounter in arguing for the persistence of chromosomes 
from one cell generation to another, and we devoted considerable 
space to the attempt to show that the commonly entertained belief 
was not really well founded (loc. cit., pp. 543-5). And with the 
advance of knowledge we, with others, have accepted the possibly 
morphological, as well as the physiological, individuality of the 
chromosomes in the spireme, as well as during other phases in 
the life history of the nucleus. 
The principal credit for the recognition of this independence of 
the chromosomes during the spireme stage of prophase belongs 
unquestionably to Gr^goire and his pupils. Nor does any dif¬ 
ference of interpretation of the events of “synapsis” seriously 
touch this claim, though it does somewhat affect the supposed 
evidence on which the generalisation itself was based. 
Professor Lawson draws attention to the well nourished 
condition of the spore mother-cells, and he appears to see in this 
accumulation of available nutrative material an explanation of the 
rapid succession of the two meiotic divisions. Discussion of the 
points raised by this or kindred suggestions would be out of place 
at the present time, inasmuch as a further paper is promised 
wherein the author expects to deal more fully with this important 
question. 
Imperial College of Science 
and Technology, December 2nd, 1912. 
RECENT WORK ON FLAGELLATA AND 
PRIMITIVE ALGiE. 
By F. Cavers. 
I—Introduction. 
rpWENTY years ago Klebs (67) 1 published the first comprehen- 
L sive work on the Flagellata in which these organisms—usually 
treated by zoological writers as a division of the Protozoa—were 
studied in detail from the botanical as well as the zoological point 
of view. Klebs pointed out that the Flagellata are a hetero¬ 
genous assemblage in which, more than in any other Protista, the 
former distinctions hitherto drawn between the animal and 
vegetable kingdoms entirely vanish; that the Flagellata may 
be regarded as a central group from which the various classes of 
Protozoa have arisen ; and that this group also embraces a number 
of specialised lines of descent—including several distinct lines 
1 References to Literature wilt be given in a Bibliography at the end of 
the concluding portion of this article. 
