Radiolaria of the Arctic Expedition, 1875-76. 435 
25. Cristellaria rotulata, Lamarck. 
Also one or two specimens approaching C. crepidula in 
contour. 
26. Polymorphina lactea, Walker & Jacob. 
Both typical pyriform specimens, and the compressed modi- 
fication known as P. lactea, var. amygdalo¢des, Reuss. 
29. Polymorphina acuminata, D’Orbigny. (Pl. XX. fig. 5, 
a, 6.) 
30. Polymorphina rotundata, Bornemann. (Pl. XX. fig. 6, 
a, 6.) 
Two interesting and somewhat rare forms, sufticiently illus- 
trated by the figures. It is necessary, however, to bear in 
mind that the successive modifications of the genus Polymor- 
phina, though generally pretty easily recognized, are of little 
more than varietal significance. 
32. Globigerina bulloides, D’Orbigny, var. 
(Pl, XX, fie, 10, 0, 8, .¢:) 
Occasional specimens of the genus Globigerina occurred in 
most of the soundings ; in one only were they present in suffi- 
cient abundance to constitute what we are accustomed to speak 
of as a Globigerina-ooze, namely in that from the most 
northerly point attained by the Expedition. The specimens 
differ considerably from the typical form—so much so that they 
can hardly be associated with it except as a variety. The 
shells are very small, compactly made, and nearly spherical ; 
the individual segments are scarcely ventricose, and do not 
exhibit the globular contour that we are accustomed to regard 
as characteristic of the genus, nor do they open into a central 
or umbilical vestibule, but communicate directly with each 
other. The general aperture forms a semicircular or crescen- 
tic opening at the inferior margin of the terminal chamber. 
The Rev. A. M. Norman probably alludes to the same modi- 
fication of the type in his description of specimens from a 
depth of 1750 fathoms in lat. 59° 10! N., long. 50° 25! W., 
one of the ‘ Valorous’ stations just within Davis Straits*. 
34. Uvigerina pygmea, D’Orbigny, var. 
(PE! XX fig. 7,/a; 8.) 
The Uvigerine, a very few specimens of which were found 
in several of the soundings, are uniform in their characters and 
* Proc. Roy, Soe. vol. xxv. p. 212. 
