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Explanation of plates. Botrychium obliquum. 
Photograph I. Young sporophyte in longitudinal section; still 
surrounded by the prothallus. The haustorium is visible at 
the lower left hand side. The cotyledon and one leaf are 
already developed. 
Photograph I[. Young sporophyte in longitudinal section. 
The prothallus is visible at the right hand side, the vascular 
bundle of the cotyledon is plainly visible. The bundle of 
the second leaf is still in the cambial stage. At the base of 
the third leaf a conspicuous apical cell may be traced. 
Photograph III. Young sporophyte in cross section. Vascular 
bundle of first root in cross section. Apical cell of second 
root conspicuous. Sheath at right hand side is remnants of 
prothallus. 
The photographs were madewith a Leitz outfit; projection 
ocular 2, bellows 50 cm, objective A. A blue filter was used 
between the arc and the condensor. 
The figures were drawn with a Zeisz drawing apparatus 
and reduced to */4 of their original size. In the following table 
the lenses will be named with which the object was observed 
(ao. 2 means objective a; ocular 2). Fig. |, size 4 cm; 
2, 2 cm: 3, a. 2: 4, F.2:5,F.2: 6, D..4;7, D. 4:8 D 
9, F.2; 10, F.2; 11, nat. size; 12, nat. size; 13, nat. size; 
14 A0 2: 15, a01.2: 16, D: 4:17, à- 2:18, Fr 22100 
20, 2 m:; 2i, | m; 22, nat. size: 23, ao. 4; 24, D. 2: 25, D .2; 
26, D: 2:27, D:.2; 28,.F.2: 29 F:.2;: 30, F-25007 
32,0% 2:33, F.2: 34,AÀ 72:35, À.2:.36, À 228780 
38, ao. 2: 39, ao. Z: 40, &o. 2: 41, 2 m; 42, 112 cm: 43, &. 4; 
44, ao. 4: 45, D. 4: 46, F .2; 47, F.2:; 48, F.2: 49, A4; 
