62 
THE TOY AGE OF H.M.S. CHALLENGER. 
Sub-family 3. Hauerininse, — test dimorphous ; chambers partly Milioline, partly 
spiral or rectilinear. 
Chambers Milioline at the commencement, subsequently 
in a straight series, ..... 
Early chambers partly Milioline and partly planospiral, 
later segments in straight series, 
Comus'pira-Yike, at the commencement, subsequently 
with two or more segments in each convolution, 
Chambers Milioline at the commencement, subsequently 
planospiral, with more than two segments in each 
convolution, ..... 
Chambers equitant, otherwise arranged as in Hauerina ; 
the lateral alar prolongations of the latest convolu- 
tion enclosing the previous whorls, . 
Articulina, d’Orbigny. 
Vertebralina, d’Orbigny. 
Ophthalmidium, Kiibler. 
Hauerina, d’Orbigny. 
Planispirina, Seguenza. 
Sub-family 4. PeneroplidinaB, — test planospiral or cyclical, sometimes crosier- 
shaped, bilaterally symmetrical. 
A planospiral tube, undivided, .... Cornuspira , Schultze. 
Chambers undivided ; arrangement either planospiral 
throughout, or spiral only at the commencement, 
subsequently becoming rectilinear or cyclical, . Peneroplis, Montfort. 
(Sub-genera — Archiacina, Broeckina, BroecJcella, Mun.-Chal. MS.) 
Chambers subdivided by transverse secondary septa ; early 
segments embracing ; arrangement either planospiral 
throughout or partly cyclical; contour nautiloid, 
auricular, crosier-shaped, or complanate, . . Orbiculina, Lamarck. 
Test discoidal ; either spiral (non-embracing) just at the 
commencement, or with one or more inflated prim- 
ordial chambers ; subsequently cyclical ; chambers 
more or less regularly divided into chamberlets, . Orbitolites, Lamarck. 
Sub-family 5. Alveolininse, — test spiral, elongated in the line of the axis of 
convolution, chambers divided into chamberlets. 
Test subglobular, elliptical, or fusiform ; recent species 
often with subdivided chamberlets, . . Alveolina, d’Orbigny. 
