202 
EXPLANATION OF PLATES. 
XXXIII. 
Genus. Tetragraptus. Salter. 
1a-c. — Tetragraptus approximatus, Nicliolson. 
la. —Fairly well preserved specimen showing distal thecae (plesio- 
type) X 2. Reverse view, Lancefield zone (Rl). Collected 
by W. H. Ferguson, Geol. Surv. Collection 18594. 
lb. —Specimen indifferently preserved bnt shewing parallelism 
of stipes and symmetry of polypary (plesiotype) x 2, Re¬ 
verse view, Bald Hill Quarry, Dromana, Bendigo zone. 
Collected by W. H. Ferguson, Geol. Surv. Collection 1167. 
l c. —Distorted specimen (plesiotype) x 2. Reverse view. One 
Tree Hill Syncline, Bendigo, Lancefield zone (Ll). Col¬ 
lected by R. A. Keble, Geol. Surv. Collection 
2a-c. — Tetragraptus acdinmis, sp. ncv. 
2a. —Large specimen (holotype) indifferently preserved but 
showing general aspect of polypary x 2|. Reverse view. 
Lightning Hill Anticline, east of Great Extended 
Hustler’s Mine, Bendigo. Collected by E. O. Teale, Geol. 
Surv. Collection No. 2763. 
2b. — Specimen with three stipes oompressed with thecae down¬ 
wards (paratype) x 2. LIustler’s Hill, Bendigo, Lance¬ 
field zone (Ll). Collected by R. A. Keble, Geol. Surv. 
Collection 
2c.—Two opposite stipes only preserved, presenting the aspect of 
Didymegraptus (paratype) x 2. Flag Syncline, Valentine- 
street, Bendigo, Lancefield zone (L2). Collected by R. 
A. Keble, Geol. Surv. Collection 
XXXIV. 
1a-e, — Tetragraptus decipiens, T. S. Hall. 
la. Polypary preserved in relief showing distal thecae and 
coenosarcal canal (plesiotype) x 2. Reverse aspect. 
Boolara-Lancefield zone (Ll). Collected by W. H. 
Ferguson, Geol. Surv. Collection No. 18609. 
lb. —Large polypary (plesiotype) x 2. Reverse aspect. Lance¬ 
field, Lancefield (Lower) zone. Geol. Surv. Collection No. 
34. 
l c. —Common appearance of polypary (plesiotype) x 2. Reverse 
aspect. Lancefield, Lancefield (Lower) zone. Geol. Surv. 
• Collection No. 238. 
ld. —Reverse aspect showing different modes of preservation of 
stipes in single specimen (plesiotype) x 2. Boolara, 
Lancefield zone (Ll). Collected by W. H. Ferguson, 
Geol. Surv. Collection No. 18555. 
le. —Distorted polypary (plesiotype) x 2. Obverse aspect. 
Lancefield, Lancefield (Lower) zone. Geol. Surv. Collec¬ 
tion No. 236. 
By Authority ; Albert J. Miillett, Government Printer, Melbourne. 
