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DOUGLAS HOUGHTON CAMPBELL 
short rhizoids which are generally in bunches separated by considerable 
areas nearly or quite bare of rhizoids (fig. i, A). 
Fig. I. A. Female plant of Podomitrium Malaccense seen from below, showing 
the branch 9 bearing a young sporophyte, X 2. B. A plant bearing a ripe sporo- 
phyte which has opened by two free valves; the base of the seta is enclosed in the 
perianth, per, and the involucre, in. C. A young archegonial branch seen from 
below, X 16. D, E. A somewhat older branch split through the middle of the arche- 
gonial group — L, lamina of the shoot; in, the involucre; per, the undeveloped 
perianth. 
The anatomy of the thallus is almost identical with that of Blyttia. 
The clearly defined midrib is composed of several thicknesses of small 
cells while the lamina has but a single layer of larger cells. Traversing 
the midrib is a strand of narrow^ thick-walled, pitted cells, closely 
resembling the corresponding tissue in Blyttia (fig. 2, C, D). 
