XVIII LIST OF ILLUSTEATIONS. 



Page. 

 Corynotrypa ahrupta. a and b, portions of the type-specimen, X 9 and X 20, 

 incrusting a fragment of Rhynchotrema capax. Richmond group. Iron Ridge, 



Wisconsin 517 



Corynotrypa ahrupta. a and h, portion of a zoarium, X 9 and X 20, incrusting 

 a crinoid column. Early Silurian, Lyckholm formation, Kertel, Island of 



Dago, Baltic Sea 518 



Corynotrypa curta. a and b, portion of a crowded zoarium, X 9 and X 20, 

 incrusting the bryozoan Lioclemella solidissima; c, fragment of a zoarium 



growing more normally, X 20. Richmond group. Savannah, Illinois 518 



Corynotrypa medialis. a, a part of the type-specimen, X 9, incrusting a cystid 

 plate; b, several zooecia of same, X 20. Richmond group, 3 miles north 



of Spring Valley, Minnesota 519 



Corynotrypa turgida. a and h, the type-specimen, natural size and X 9. Rich- 

 mond group (Fernvale formation), Wilmington, Illinois, c, a specimen, X 9, 



from the Richmond group, 3 miles north of Spring Valley, Minnesota 520 



Corynotrypa devonica. a, one of the type-specimens, X 7; b, portion of the 



same, X 12. Devonian, Department de la Mayenne, France 521 



Corynotrypa smithi. Part of the type-specimen, incrusting a cardium. Juras- 

 sic, Bathonian, near Scarborough, England 522 



Corynotrype dissimilis. a and b, a typical example of the species, X 9 and X 20, 

 incrusting the epitheca of the bryozoan Diplotrypa nummiformis . Silurian, 

 Rochester shale, Lockport, New York, c and d, a poorly preserved specimen 

 of the species, X 9 and X 20, growing upon a specimen of heliolites. Early 



Silurian, Lyckholm formation, Kertel, Island of Dago, Baltic Sea 523 



Corynotrypa dissimilis. a and b, portions of a zoarium, X 9, parasitic upon a 

 fragment of a sptrifer. Silurian, Rochester shale, Lockport, New York. This 



specimen illustrates branching at right angles 524 



Corynotrypa tennesseensis . a, the type-specimen, X 9, with a longitudinal sec- 

 tion of several zooecia; b, several zooecia X 20, incrusting a fragment of a 

 strophomena. Ordovician, Stones River group. Pierce limestone, one-half 



mile south of Murfreesboro, Tennessee 525 



Corynotrypa schucherti. a and b, portions of the type-specimen, incrusting a 

 Streptelasma, X 9; c, several zooecia of the same, X 20. Middle Ordovician, 



Wesenberg formation, Wesenberg, Esthonia, Russia 525 



Corynotrypa canadensis, a, portion of type-specimen, X 9; b, front and side 

 views of a zooecium, X 9. Middle Ordovician, Swampy Island, Lake Win- 

 nipeg, Canada 626 



Eumeta intercalaris Carpenter 566 



Eumeta bimarginata C. B. Adams 566 



Eumeta eucosmia Bartsch 568 



Crotalus willardi. 1^ X natural size. 1, top of head; 2, side of head; 3, under- 

 side of head; 4, head from front 569 



Characteristic shapes of the rutile inclusions in mica. Greatly magnified 574 



Diastoma fastigiata Carpenter 582 



Diastoma chrysalloidea Bartsch 583 



Diastoma oldroydse Bartsch 583 



Diastoma stearnsi Bartsch 584 



Dipachystigma cushmani. Antenna of female 619 



Dipachy stigma cushmani. Fore ring of female 619 



Winnemana argei. Antenna of female 620 



Genitalia of male Nomada tezana Crucis 653 



