Leg-end. g. Umlional scans. c. Concrete centrals. 



" -  " Transmedian seal's. 



Cardinal area. 

 Median septum. 

 Lateral septa. 

 Vasculai- trunks. 

 Vascular branches. 



LINGULA, BRUGuifeRE. 



Page 2. 



Glossina, Phillips. 



Page 1"). 



LiNGULA (Glossina) acuminata, Conrad. 



Fip. 1. A pedicle-valve from which most of the substance of the shell has been exfoliated, presenting- a 

 iMst of the internal surface, .which retains the impressions of the tine radi;itin>,', and coarser, 

 moie distinct, concentric lines. The thickness of the shell-substance and the undulating char- 

 acter of its laminae, is shown on the mai'ginal portion of the tig-ui'e, but no traces of muscular 

 inijiressions are disceniible. X 2. 



Fig-. 2. A brachial valve of the same species, from which the shell is partially exfoliated. X 2. 

 Calcifei'ous sandstone. iSarafneja, N. Y. 



LiNGULA (Glossina) ricinifokmis, Hall. 



Fig-. 'A. A pedicle-valve (l) from which the outer laj'ers of the shell are somewhat exfoliated ; showing- the 

 strong median radii, which are evidently more distinctly developed on the iiiterioi- than on 

 the exterior of the shell. X 3. 



Trenton limestone. Middleville, N. Y. 



LiNGULA Vanhoknii, Millor. 



Fig. 4. The interior of a pedicle-valve ; showing the undifferentiated lateral muscular scars, and the low, 

 median septum. X 3. 



Hn<lson River group. Cincinnati, Ohio. 



LiNGULA Pkocteri. Uliich. 



Fig. a. The brachial \-alve of an internal cast : showing the concrete latei'als (x), the anterioi- laterals (j), 



and the septum (s). X 1-"). 

 Fig. 6. The opposite \alve of the same specimen ; showing the progressive lateral and median impres- 

 sions (septum) and the va.sculai- markings. X L5. 



Hudson River' gronji. Sonfh Cmyingtov, Knitncky . 

 Fig. 7. An internal cast of a brachial valve ; showing the lateral scars and long median septum. X 2. 

 Hudson River.'gTOup. Oineinnati, Ohio. 



LiNGULA Philomela, Billings. 



Fig. S. A pedicle-vahe ('fj, imperfect in the umbonal I'egion ; illustrating one extreme of outline attained 

 by shells of this genus. Natural size. 



Trenton limestone. Florencnnllc, Hovxird county, Imva. 



LiNGULA LAMELLATA, Hall. 

 Figs. 0, 10. Extei-nal and internal views of the same specimen. Natural size. 

 Niagara group. Lovkpnrt, JV. Y. 



LiNGULA CUNEATA, Coiliad. 



Fig. 11. An internal cast of the pedicle-\alve ; showing the broad, low, median septum and thi? faint lateral 

 scai-s. X 2. 



Fig. 12. The brachial valve, with an ill-defined muscular scar and traces of the vascular sinuses. 



Mediiui sandstone. Albion, JV. Y. 



