ORTMANN ! TERTIARY INVERTEBRATES. 
87 
Remarks : v. Ihering distinguishes two species, C. alta and daili, which 
I believe to be identical : in order to support my opinion, I give here 
detailed measurements of 14 good specimens out of our material (Nos. 1, 
2, 4, 9-14 from Santa Cruz, Nos. 3, 5-8 from Mt. of Observation). 
- Number. 
Length. 
Height. 
Distance of Apex from 
Ant. End. 
Width of Area. 
Number of Sulci. 
I 
22 
18 
9 rel. i : 2.4 
? 
I 
2 
50 
41 
19 “ 1 : 2.6 
5 
3 
3 
64 
58 
24 “ 1 : 2.6 
8 
4 
4 
65 
5 6 
26 “ 1 : 2.5 
7 
5 anter., 4 poster. 
5 
65 
58 
24 “ 1 : 2.6 
9 
4 
6 
67 
58 
27 “ 1 :2.5 
8 
3 
7 
69 
59 
25 “ 1 : 2.7 
8 
3 
8 
7 1 
62 
27 “ 1 : 2.6 
8 
5 
9 
7 2 
62 
33 “ 1:2.2 
1 1 
7 anter., 6 poster. 
10 
79 
67 
35 “ 1 : 2.2 
10 
5 
1 1 
80 
66 
31 “ 1 : 2.6 
9 
6 
12 
83 
73 
40 “ 1 : 2.1 
15 
7 anter., 8 poster. 
13 
85 
73 
29 “ 1 : 2.9 
14 
7 
1 4 
88 
73 
33 “ 1:2.6 
12 
6 anter., 5 poster. 
In 1897, v - Ihering mentioned as distinctive characters betwen C. mul- 
ticostata and daili the following: (1) External form, (2) sculpture of shell, 
(3) number of sulci of the area, (4) size. In 1899 he modified his state- 
ments as to the third character : he says that a shell of C. alta (which he 
unites with C. multicosta fa) of 45 mm length has an area 7 mm broad, 
with 9 sulci, while C. daili at a length of 50 mm has an area 5 mm broad, 
and only two sulci. This looks certainly like a striking difference. His 
C. multicostata ( = alta) of 1897 38 mm. long, and has only two sulci. 
Among our specimens, one (No. 2), of the same size (50 mm) as the 
individual of C. daili just mentioned, has only 3 sulci, and this number 
hardly increases in the specimens Nos. 3-8 (length from 64 to 71 mm): 
there are only 3 to 5 sulci, and specimens Nos. 10 and 1 1 (length 79 and 
80 mm) continue this series regularly with from 5 to 6 sulci. 
. But No. 9 is outside of the series ; its size is hardly larger than that of 
No. 8, but the sulci of the area number 6, or 7. Although this specimen 
must still be classed with v. Ihering’ s C. daili , it shows clearly that some- 
times in individuals of comparatively smaller size the number of sulci may 
be exceptionally high. On the other hand, we see in No. 14, that in 
comparatively large individuals the number of sulci may remain very small 
