PLATE 11-1 



1 — Coccolith, schematic drawing of a coccosphere, diameter 10 microns, Jurassic to Recent. 



2 — Dictyocha sp., diameter 76 microns, Tertiary, California. 



3 — Naviculopsis sp., size 19 x 168 microns, Tertiary, California. 



4 — Vallacerta sp., diameter 58 microns, Cretaceous, California. 



5 — Gonyaulax jurassica Deflandre ( ? ) , length 100 microns, Curtis formation, Upper Jurassic, 

 Utah. 



6 — Actinoptychus sp., diameter 94 microns, Tertiary, California. 



7 — Triceratium sp., diameter 85 microns, Tertiary, California. 



8 — Suriella sp., size 80 x 180 microns, Tertiary, California. 



9 — Coscinodiscus sp., diameter 82 microns, Tertiary, California. 



10 — Biddulphia sp., size 60 x 228 microns, Tertiary, California. 



11 — Triceratium sp., length 90 microns, Tertiary, California. 



12 — Aclistochara clivulata Peck and Reker, lateral view, length 1 mm., Middle Eocene, Flori- 

 da. (Peck and Reker, Jour. Paleontology, v. 22) 



13 — Aclistochara clivulata Peck and Reker, basal view, diameter 0.87 mm., Middle Eocene, 

 Florida. (Peck and Reker, Jour. Paleontology, v. 22) 



14 — Aclistochara coronata Peck and Reker, lateral view, length 0.73 mm., Lower Eocene, Wyo- 

 ming. (Peck and Reker, Jour. Paleontology, v. 22) 



15 — Pediastrum kajaites Wilson and Hoffmeister, diameter 132 microns, Lower Formation 

 (Paleogene), Sumatra. 



16 — Cuticle type A Wilson and Hoffmeister, cell size, length 39-58 microns, width 5-18 

 microns, Middle Pennsylvanian, Oklahoma. (Okla. Geol. Survey, Circular 32) 



17 — Sporange cuticle, cell size, 80 x 180 microns, Tertiary, Wyoming. 



18 — Abitineae type border pits, size 20 x 58 microns, diameter of pits 18 microns, Mesozoic 

 (?), Florida. 



19 — Staurastrum paradoxum Meyen, diameter 1 mm. (fresh-water algae of the United States, 

 Smith 1950). 



20 — Chamaedaphne calyculata, size 31 x 40 microns, Pleistocene, Massachusetts. 



21 — Unicellular trichome, size 12 x 72 microns, Pleistocene, Massachusetts. 



22 — Sheperdia canadensis, fragment, diameter 430 microns, Pleistocene, Massachusetts. 



23 — Sponge spicule, size 96 x 220 microns, Tertiary, New Zealand. 



24 — Sponge spicule, size 24 x 140 microns, Cretaceous, California. 



25 — Sponge spicule, size 24 x 158 microns, Tertiary, New Zealand. 



26 — Sponge spicule, size 13 x 240 microns, Tertiary, New Zealand. 



27 — Alcyonarian spicule after Wright, size 1-3 mm., Recent. (Principles of micropaleontology, 

 Glaessner 1944) 



28 — Alcyonarian spicule after Pocta, size 1-3 mm., Upper Cretaceous, Bohemia. (Principles of 

 micropaleontology, Glaessner 1944) 



29 — Theelia undulata (Schumberger), diameter 0.20 mm., Eocene, France. (Frizzell and 

 Exline, Missouri School of Mines Tech. Ser., No. 89, 1955) 



30 — Rhabdotites mortenseni Deflandre-Rigaud, length 1.02 mm., Jurassic, Germany. (Frizzell 

 and Exline, op. cit.) 



31 — Binoculities terquemi Deflandre-Rigaud, length 0.56 mm., Jurassic, Germany. (Frizzell 

 and Exline, op. cit.) 



32 — Synaptites eocoenus (Schlumberger), length 0.18 mm., Eocene, France. (Frizzell and 

 Exline, op. cit.) 



210 



