500 
Transactions of the Society. 
grammostomum Reuss, 1867, Sitzungsb. k. Akad. Wiss. Wien, 
yoI. lv. Abth. i. p. 72, pi. ii. fig. 5. Biloculina ventruosa Eeuss, 
1867, ibid., p. 69, pi. i. fig. 9. Miliolina circularis (Born.) Egger, 
1893, Abhandl. k. bayer. Akad. Wiss., Cl. II. vol. xviii. Abth. ii. 
p. 235, pi. ii. figs. 61-63. M. circularis (Born.) Jones, 1895, 
Palaeontographical Soc., p. 121, pi. v. fig. 4. 
Continuing with the forms which typically have the chambers 
round or crescentiform in cross section, by imperceptible degrees 
changing into those in which the chambers become angular or cari- 
nate, we have now to treat of the short robust forms, in which the 
long straight chambers characteristic of M. oblonga are replaced by 
short ones, more or less curved. 
M. subrotunda would almost as well have served for the type ; but 
on the whole M. circularis appears to possess a larger number of the 
characters common to the group. As shown, by the figures on plate 
XI., it exists in the Biloculine, Triloculine, and Quinqueloculine forms, 
all of which are edentate and have an aperture formed simply by a tent- 
like fold of the last added chamber, leaving the surface of the penulti- 
mate chamber exposed. 
The Biloculine form, fig. 2, appears to be the B. ventruosa of 
Reuss. Although the specimen selected for illustration approaches 
Biloculina sjrfizera d’Orbigny, there are many others which are 
identical with B. ventruosa as figured by Reuss. Fig. 1 is the Tri- 
loculina circularis of Reuss, whilst the Quinqueloculine form, fig. 3, is 
scarcely separable from Miliolina subrotunda Montagu. The admi- 
rable researches of MM. Schlumberger and Munier-Chalmas show 
that individuals of the Miliolinae in various stages of growth assume 
Biloculine, Triloculine, and Quinqueloculine characters. In the exami- 
nation of a large series of specimens it is scarcely practicable to apply 
Schlumberger ’s laborious method of research ; bat there are on the 
exterior of the test certain characters, too subtle for scientific definition 
and appreciable only by a faculty we all possess which is somewhat 
akin to instinct — the kind of faculty which, to use a common illustra- 
tion, enables the shepherd to identify each individual member of his 
flock, although at the same time he is totally incapable of defining 
the minute differences which serve to distinguish one from the others. 
By the exercise of some such quality of the mind, we arrive at the 
conclusion that the three forms in question can be no other than 
variations of M. circularis. Speaking of M. jprocera , Dr. Axel Goes 
says,* “ It seems to be clearly allied to M. circularis (Bornem.) Br., 
the chief difference being its quinqueloculine arrangement of the 
chambers.” Dr. Goes has thoroughly studied the subject, and his 
opinion is of great value ; still, although fig. 3 is Quinqueloculine, it 
possesses too many of the characters of M. circularis to be separated 
from it with advantage. 
* Bull. Mus. Comp. Zoology at Harvard College, vol. xxix. No. 1, 1896, p. 82. 
