290 Chromosomes in the Spermatogenesis of Anasa Tristis 
Jongitudinal furrow is still visible. This longitudinal furrow is shown 
more clearly in Photos. 12, 16, 17, 18, 19, 20, 23, ete. 
Our Photos. 10 to 17 evidently represent the same stage of develop- 
ment shown in Wilson’s sketch k (Text Fig. 2) and Montgomery’s 
sketch 76 (Text Fig. 1), and a comparison of their sketches with our 
photographs will, we think, furnish a justification of our preference for 
our smear method. These authors designate this stage as the metaphase, 
but we have called it late prophase or metaphase because there is evi- 
dence that the chromosomes do not invariably maintain this ring posi- 
tion throughout the metaphase. Often cases are found in which the 
chromosomes are nearly or quite in a straight line at the metaphase, 
possible displacement of the chromosomes not offering an adequate expla- 
nation of this difference in arrangement. Photos. 20 to 27, Plate II, 
illustrate some of these cases. The fact, however, that the typical ar- 
rangement of the chromosomes shown for example in Photo. 12, Plate IT, 
is often maintained at the late anaphase and telophase indicates that 
the ring arrangement of the chromosomes may persist through the entire 
division. As a demonstration of this compare Photo. 12, Plate I, 
with Photos. 2, 3, and 4, Plate III. 
The characteristic position of the eccentric chromosome in Photos. 
11, 12, 138, 16, 17, 18, 19, 20, 21; and 22, Plate II, assures its identifi- 
cation and makes special reference to these photographs unnecessary. 
In Photos. 14 and 15, however, the eccentric chromosome is not outside 
but takes part in forming the circle of chromosomes and we have repro- 
duced these preparations in order to demonstrate that the eccentric, 
though typically, is not invariably found outside and apart from the 
other chromosomes. In Photo. 14 it is just below the largest chromo- 
some of the group, its longitudinal furrow serving to identify it, and 
in Photo. 15 it is also just below the largest chromosome. Some of 
these photographs show one or two dense dyads clearly differentiated 
from the eccentric. In Photo. 13 we see a dense dyad in the circle of 
chromosomes just below the largest chromosome and almost opposite the 
eccentric. In Photo. 14 we again find a dense dyad in the circle and 
opposite the eccentric. In Photo. 15 there are two such dense dyads 
present, but they cannot be confused with the eccentric which is easily 
identified by its longitudinal furrow. A dense dyad, plainly not the eccen- 
tric chromosome, is present also in Photos. 17, 19, 22, 24, and 27. In the 
light of these cases we should expect to find often one or two dense chro- 
mosomes at the telophase of the first division or prophase of the second 
and we feel justified in interpreting such chromosomes as the daughter 
