376 PROCEEDINGS OF THE ACADEMY OF [June, 
Length 12.3, diam. 4 mm. ; ; whorls 1 123; lamellee 1; ribs 27. 
11.5, 3.7 114; 2: 16. 
eet Mee Dene hy Sr 
“c 11.2, “cc 4 “c “cc 22 “cc 2; “cc 38. 
73 10.8, iz 4.2 “ce “e 113; ‘c 2; “ec 16. 
“ce iG; “ec 3.9 ce cc 113; ce iG “ce DATE 
Station 18 (Pl. XIV, figs. 3, 3a). In the third ravine west of the 
granitic spur on north side of Tweed Canyon, above a dyke of igneous 
rock about 50 yards wide. Below this dyke, at Station 17, Holospira 
campestris cochisei is found. A deep gulley or ‘‘wash”’ extends 
from the ravine upon the mesa. The shells at Station 18 are a 
little more finely ribbed than typical H. danielsi and to that extent 
approach H. campestris cochiset. Out of 16 opened, 9 shells have 
3, and 7 shells have two internal lamellae. Measurements follow. 
Length 11.3, diam. 4 mm. ; ; whorls 123; lamellee rp ribs 22. 
1.2 3. 12: 3; © 28. 
¢ ie ce 4 “ce ce ja 73 PAE ce Tae 
‘as ae ce 3.9 “c ce 123; “c 2; ce 16. 
ce 10, cc 3.5 cc “cc 1}: “ce 2; “cc ADA 
“cc 10, ce ae cc “c 113; “cc 33 “c 26. 
“cc 10, “c Bye, “cc “ce 112; ‘c af “cc 18. 
tre Oe a pee ee eee cee 22 
pies ENE te ee 
OREN he Bao ee iam te in 
“ce 9, “cc Bi cc ce 103; ce a: “cc 94. 
Station 20 (mouth of the second ravine west of granitic spur, 
Tweed Canyon). Shells similar to the preceding lot. 
Station 22 (bed of the same ravine several hundred yards above 
the mouth). Shells similar, but averaging larger, though some 
are equally small; lamelle one or two. 
Length 12.5, diam. 4 mm.; whorls 123; ribs 16. 
Dek LOSE tae us? ere age piers) i ed ae 8 
eval), ome Sia? the ee bs Ste ae 
Specimens from the southeastern part of the upper amphitheatre 
of Tweed Canyon have only one or two lamelle (parietal and axial), 
those with one slightly predominating. The parietal lamella is 
moderate or small when developed. They are also perceptibly | 
stouter in figure than the types, and the number of ribs is, in the 
main, greater. 
Station 10 (floor of the upper amphitheatre of Tweed Canyon, 
southeastern branch). Not a favorable station for Holospira, being 
shaded by a dense growth of shrubs and trees. A few specimens 
taken have one or two lamelle, and the aperture is built forward 
further than in the types. Ribs as in the following. 
