80 
and melting at 50°,5 C., was obtained from salicylaldehyde and aniline. 
The substance is dimorphous: il occurs in a less stable rhombic 
a-modification, and in a monoclinic #-form, which is obtained in 
most cases; both modifications are yellow. 
1. a-Modification. 
Fig. 5. 0-Oxy-benzylidene-aniline. 
(a-Modification). 
From ligroin this modification erystallizes in most cases in the 
form of big, yellow, almost always opaque and flattened bipyramids. 
Rhombic-bipyramidal. 
a:6:¢= 0,4729: 1: 0,2188. 
Forms observed: 0 = §111}, big, but badly reflecting; 6 = {010}, 
small, yielding good reflexes. The crystals obtained from a solution 
in methyl-alcohol showed also a prism m = {130}, the faces of which 
gave good images. 
Angular values: Observed: Calculated : 
0:0 = (111): (111) = * 22°28)" — 
0:0 — (111): A11) = * 48 39 — 
0:0 = (111): (111) = 125 55 125°47" 
Obd) (O10) = an HAEG 78 46 
mb = (130) (010) =S - 3459), <35 41 
No distinct cleavage was found. 
The specifie weight of these crystals was: 1,087 at 16° C.; the » 
equivalent-volume is thus: 181,23, and the topical parameters are 
calculated at: 7: Wp: @ = 5,7005: 12,0539 : 2,6375. 
2. 8-Modification. 
The crystals of the a-modification are easily transformed into those 
of the B-form by reerystallisation. If, however, the long needles of 
the 8-modification thus obtained, are again recrystallized from methyl- 
alcohol, they are again changed into the bipyramids of the a-form. 
