290 Prof. A. Des Cloiseaux on the three Types of Hi mite. 

 Table (continued). 



Scacchi's 



symbols. 



Symbols of 

 *Des CI. 



Miller's 

 symbols. 



Calculated 

 angles. 



Observed 



angles. 



A : w 4 



p io 



001:421 



97 23 



O 1 



97 25 



A : n v 



ph* 



1:210 



97 23 



97 25 



A:r 



pb l 



1:112 



140 14 



140 20 



A : r 2 



pd% 



00 1 :223 



136 9 



136 8 



A : r 3 



p b^ 



00 1:223 



131 23 



131 25 



A:r 4 



pd? 



001:111 



125 47 



125 50 



C:r* 



9 X &* 



10:111 



137 25 



137 28 



A : r 5 



pb* 



1:111 



119 17 



119 20 



A:r 6 



pd± 



001:221 



111 49 



111 53 



A : r 



pb± 



1:221 



103 31 



103 37 



A:r 8 



p m 



001:110 



94 35 



94 28 



C:? 3 



g l m 



010:110 



*154 48 



154 48 



«, y, e, X, <23 = t 1 posterior, t\ — t-l anterior, are represented 

 in fig. 229 of my ' Manual;' £*, e 1 , o 3 , and co are new forms 

 found by vom Rath. 



Plane of the optic axes inclined from behind forward, making 

 an angle with the base of about 11°. The acute bisectrix is 

 positive and normal to the plane of symmetry. Dispersion of 

 the axes very weak, p < v. Dispersion tournante hardly appre- 

 ciable in the most homogeneous plates. 



2H a . r =84° 38' to 85° 4f in white crystals, 



86° W to 87° U' in a yellow crystal from Monte 

 Somma. 



Internal structure more or less complex, formed by the union 

 parallel to the base of twin laminae (figs. 2 and 3). These 



White cry s teds. 



Yell Oil' CT2{Stal 



