104 ARTICULATA. 



No. 421. Harpes ungula, Ban. 



Head. From tlie Upper Silurian limestone at Kronie- 

 prus. Bohemia. The body -segments and tail are usually 

 wanting, as is the case in this specimen. Original in the 

 Ward Museum in the University of Bochester. 



Price, $0.30. 



No. 422. Harpides G-rimmi, Barr. 



From the Lower Silurian at Przibram, Bohemia. Tail wanting. 



No. 423. Homalonotus delphinocephalus, Murch. 



Price. $0.75. 



This genus is so named because the three-lobed aspect so 



fj characteristic of the family is, in a great measure, obliterated, 



gijl|i and the back appears smooth and uniform. The cephalic 



f and caudal shields are hyperbolic ; the rings number thir- 



Ifjgf teen. This species is characterized by the distinct trilobation 



of the tail in all its stages of growth, as well as by its slender 



body T and acute caudal extremity. The specimen is from the 



Upper Silurian at Dudley, Eng. Size, 7x4. Price, $1.25. 



No. 424. Homalonotus Dekayi, Green. 



This species is from the Hamilton Group (Devonian), Madison Co., N. Y. 



Size, 7x4. Price, $1.25. 



No. 425. Illasnus crassicauda, Daim. 



This trilobite (coiled) shows finely the broad spherical buckler or cephalic 

 shield. The original, from the Lower Silurian of Christiania, Norway, is in the 

 private Geological Cabinet of Mr. Ward, Bochester. Price, $0.40. 



No. 426. Illaenus giganteus, Brong. 



The general form of this species is variable from its contractility. It has ten 

 articulations ; prominent eyes ; and large, convex buckler and caudal shield. 

 This specimen is from the Lower Silurian, Angers, France, and is in the Ward 

 Museum of the University of Bochester. Size, 7x7. Price, $1.00. 



No. 427. Illsenus Taurus, Hall. 



This Trilobite (coiled) is from the Trenton Limestone (Lower Silurian), Min- 

 eral Point, Wisconsin. Price, $0.50. 



