Wachsmuth and Springer—Palwocrinoidea. 365 
V.0; A320; P20; PbO cant ZnO HO 
Tritochorite, Frenzel G., 6°25 24°41 3°76 .... 53°90 7:04 11°06 .... = 100-17 
Descloizite, Penfield, 6-205 18°95 3°82 0-18 54°93 6-74 12:24 2-70 
It does not seem probable that 2°70 per cent of water could 
have been overlooked in the analysis of tritochorite and the dif- 
ference in the percentage of vanaiic acid in the two minerals is 
also quite large. Nevertheless, the minerals are so much alike 
in all physical characters, that it may be possible that they are 
‘identical: But more definite facts in relation to the occurrence 
of the minerals and further analyses are necessary in order to 
- decide definitely the relation between 
2 Sheffield Scientific School, June 23d, 1883. 
4 
Art. XLI.—On Hybocrinus, Hoplocrinus and Berocrinus ; 
by CHARLES W icuaunee and FRANK SPRINGER. 
WHEN we prepared the generic description of Hybocrinus 
for the first part of our Revision of the Paleocrinoidea, we 
were not aware that the Duke of Leuchtenberg had. de- 
scribed a species from Russia under the name of Apiocrinus 
Hipontos which had been referred by several writers to the 
ormer genus. Our first knowledge of the occurrence of this 
enus in Russia was derived from Professor Zittel’s Ha ae 
er Palxontologie, received Dee our work was in press, i 
yy P. Herbert ena in his late paper “On the Relation of 
Ga meri ieme! and Hybocytites,” published in the 
, London, August, 1882, page 292. 
ney found it “ tather curious” that we had not observed 
the differences existing among the az azygous plates of the Rus- 
sian and Can ye species, ar while quoting Hoplocrinus and 
@rocrinus as synonyms of ee aden ad not noted the 
Species deaeribed under those gene 
We have since .o Dik tii ah examine the numerous 
Publications which bh. en on these genera and have 
come to the peas that th Russian dead wee d be se Pp 
arated from Hybocrinus even more than subge y: 
The genus Hybocrinus, as originally defined Oy pee is 
Am. Jour, So1.—Turep Serres, VoL. XXVI, No. 155.—Nov. 
