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ANNALS NEW YORK ACADEMY OF SCIENCES 
the adult of Streptelasma profundum, with figures 10 to 12 of Strereolasma 
rectum, etc. The counter quadrants are accelerated over the cardinal quad¬ 
rants as was the case with all the species previously discussed, four pairs of 
secondary septa having already appeared in the counter quadrants while 
only two pairs have appeared in the cardinal quadrants. In figure 2, the 
arrangement and development of the septa is still very similar to that found 
in the Streptelasma forms. Another secondary septum has appeared in 
one counter quadrant and another pair in the cardinal quadrants. No 
special indication of this particular species has yet appeared. It will be 
noted, however, that the septa do unite at the center to form a sort of pseudo¬ 
columella, but this character is not as yet any more marked than in Stereo- 
lasma rectum. In the section shown in figure 3, the form is distinctly marked 
as a Lophophyllum by the columella-like thickening at the inner end of the 
counter septum. An additional pair of secondary septa have appeared in 
both counter and cardinal quadrants, and the cardinal septum is becoming 
reduced in size. In figure 4, a section cut from the base of the open cup, 
we have a condition very similar to the adult condition found in Heterophrentis 
prolifica, except for the columella-like thickening at the end of the counter 
septum. The cardinal septum is very short. The other three primary 
septa are more prominently developed than any of the secondary septa. 
Figures 5 to 11 represent the series of developmental stages of this 
same species, copied from Duerden. Figure 5 is from the tip of a coral 
individual and shows the earliest stage which w T as obtained. The four 
primary septa are present, and one pair of secondary septa have already 
appeared in the counter quadrants. Figure 6 is a section from a second 
individual at a higher level showing a later stage. In this another secondary 
septum has appeared in one counter quadrant, and one has appeared in the 
cardinal quadrant of the same side. Figure 7 is a section from a third indi¬ 
vidual at a still higher level. Two secondary septa have appeared in one 
counter quadrant, three in the other and one in each cardinal quadrant. 
Figures 8, 9 and 10 are sections from the same individual as figure 7, show¬ 
ing the later stages and the rate and manner of the addition of the secondary 
septa. Figure 10 illustrates a stage intermediate between that shown in 
figure 3 and that in figure 4. Figure 11 is from the upper region of a fourth 
individual and illustrates the final adult condition. 
We thus see that the genus Lophophyllum in its individual development 
first passes through stages corresponding to the life history of the Strepte- 
lasma-Stereolasma line, then through a stage equivalent to the Heterophrentis 
stage characterized by a waning cardinal septum and very prominent fossula, 
and in its adult condition adds a new and specialized character, the col¬ 
umella-like thickening at the inner end of the counter septum. This genus 
