292 BULLETIN 88, UNITED STATES NATIONAL MUSEUM. 



FIG. 4. Mesopalseaster intermedius, new species. 



Photograph X 3 of the holotype. Between the two rays lies an arm of 

 a crinid, giving the impression that this form has a large disk. 

 Upper Ordovicic (Maysvillian). Cincinnati, Ohio. 

 Collection of the University of Chicago (No. 9575). 

 FIG. 5. Mesopalseaster finei (Ulrich) (also see plate 7). 



Ulrich's original figures. Fig. 5, one of the cotypes from the abactinal 

 side X 2; fig. 5a, the madreporite X 6; fig. 56, a ray from the actinal side X 3. 

 Upper Ordovicic (Eden). Cincinnati, Ohio. 



Ulrich collection of the United States National Museum (Cat. No. 60604). 

 FIG. 6. Mesopalseaster caractad (Gregory) (also see plate 11). 



Retouched photograph X 3 of a wax squeeze by Bather, now in the 

 United States National Museum (Cat. No. 60606). Actinal area. 

 Ordovicic (Caradoc). Church Stretton, England. 



PLATE 10. 



FIGS. 1 and 2. Mesopalseaster clarki (Clarke and Swartz). 



1. Drawing of the actinal side of the holotype X 1.5. 



2. Abactinal area X 1.5. Note the few accessory pieces in the angles 

 between the radials. 



Upper Devonic (Chemung). Near Oakland, Maryland. 

 Collection of the Maryland Geological Survey. 



PLATE 11. 



FIG. 1. Mesopalxaster caractad (Gregory) (also see plate 9). 



Retouched photograph X 3 of a wax squeeze by Bather, now in the 

 United States National Museum (Cat. No. 60606). Abactinal area. 



Ordovicic (Caradoc). Church Stretton, England. 

 FIG. 2. Devonaster chemungensis, new species. 



Photograph of the natural mold of the actinal side of the holotype, 

 natural size. 



Upper Devonic (Chemung). "Central Pennsylvania." 

 CoUection of Columbia University (No. 6228G). 



PLATE 12. 



FIGS. 1 and 2. Spaniaster latiscutatus (Sandberger). 



1. Abactinal side. 



2. Actinal side. 

 After Schondorf . 



Lower Devonic. Germany. 

 FIGS. 3-5. Devonaster eucharis (Hall). 



3. Abactinal side, natural size, a, the madreporite. After Hall. 



4. Actinal side, natural size. After Hall. The tiny ambulacral plates 

 should have been drawn as opposite one another and not alternate. 



5. Hall's diagram (3a) of the actinal plate arrangement. The ambu- 

 lacrals are incorrectly drawn, as their arrangement is opposite and not 

 alternate, a, ambulacralia; aa, adambulacralia; m, inframarginalia; o, 

 pairs of oral armature ossicles; p, podial openings, but drawn a little too 

 large; tm, the single interbrachial axillaries. 



Middle Devonic (Hamilton). Near Hamilton, New York. 



