WILLIAMS AND 
KINDLE. 
FAUNULES OF CATAWISSA SECTION. 
75 
Zone 21^ of Catawissa section (H53 A). — A f ossiferous band 6 inches 
thick contains the following faunule: 
Faunule of zone 24 of Catawissa section {1453 A). 
[a, abundant; c, common; r, rare.] 
1. Crania sp. (r). 
2. Stropheodonta (Leptostrophia) inter- 
strialis (c). 
3. S. (L. ) perplana var. nervosa (a). 
4. Chonetes setigerus (r). 
5. Schizophoria striatula (c). 
6. Cortina hamiltonensis (c). 
7. Spirifer pennatus var. posterus (a). 
8. Glyptodesma erecturn (r). 
9. Pleurotomaria sp. (r). 
10. Tentaculites spiculus (r). 
Zone 25 of Catawissa section (1^53 A). — This zone comprises 18 feet 
of bluish-gray sandy beds, sparingly fossiliferous. 
Zone 26 of Catawissa section (14-53 A). — Following the preceding 
zone are 3^ feet of beds, which hold the following faunule: 
Faunule of zone 26 of Catawissa section ( 1453 A ) . 
[a, abundant; c, common; r, rare.] 
1. Cystodictya meeki (c). 
2. Stropheodonta (Leptostrophia) inter- 
strialis (r). 
3. S. (L. ) perplana var. nervosa (a). 
4. Chonetes scitulus (c). 
5. Productella speciosa (r). 
6. Atrypa reticularis (a). 
7. Cyrtina hamiltonensis (c). 
8. Spirifer pennatus var. posterus (a). 
9. Leiopteria cf. bigsbyi (r). 
10. Actinopteria perstrialis (a). 
11.' Tentaculites spiculus (c). 
The specimens here listed as Sp. pennatus var. posterus exhibit some 
interesting variations. Some of the specimens which represent the 
posterus type have the well-marked muscular impression in the ventral 
valve characteristic of this form, without any distinct trace of a median 
septum which characterizes the closely related form Delthyris mesicos- 
talis. A few have the weakly developed median septum without the 
muscular impression, and represent an early stage of development of 
Delthyris mesicostalis. A majority of the specimens show both char- 
acters, the median septum being but slightly developed in any indi- 
viduals. 
Zone 27 to 30 of Catawissa section {H53 A). — Three hundred and 
sixty -three feet of nearly barren beds succeed the last zone. 
Zone 31 of Catawissa section {1J{S3 A). — Five feet of olive-gray sandy 
beds afford the following species: 
Faunule of zone 31 of Catawissa section (1453 A) . 
[a, abundant; c, common; r, rare.] 
1. Productella speciosa (r). 
2. Schizophoria striatula (a). 
3. Pugnax cf. pugnus (r). 
4. Atrypa aspera (r). 
5. A. reticularis (c). 
The third species is represented by two small fragments doubtfully 
referred to this species. 
