24 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 



This species resembles the questionable variety subconstricta Gru- 

 now of A. lineata Gregory, a fresh-water form figured in Diatoms 

 of the Caspian Sea, plate 3, figure 5, but has relatively much coarser 

 markings and blunter ends. The true A. lineata is a widely different 

 form, and is given in Diatoms of the Clyde, page 512, plate 12, figure 

 70. It also slightly resembles A. philippinica Castracane (Chall. 

 Exp., pi. 27, fig. 2), which on account of its original locality being 

 identical with that of this form, deserves consideration; but Castra- 

 cane's species is much narrower, has "apices that are very prolonged, 

 sharp and slightly bent" and "striis transversis perspicuis punctu- 

 latis." The two, therefore, can not be confused. 



It is named in honor of Mr. Henry W. Henshaw, who found the 

 first specimen. 



Type.— Cat. No. 43576, U.S.N.M. 



AMPHORA HYALINA Kiitzing 



(Schmidt, Atlas, pi. 26, figs. 52-55; H. L. Smith, Types, No. 614.) 



AMPHORA INFLATA Grunow 



(Schmidt, Atlas, pi. 25, figs. 29-30.) 



The original of this also was from Campeche Bay. 



AMPHORA INTERSECTA A. Schmidt, yar.? 



Plate 5, fig. 6 

 (Schmidt, Atlas, pi. 25, figs. 37-38.) 



I give a figure of what may be a coarse variety of the above species. 

 The differences hardly warrant a separate name, but Schmidt's speci- 

 mens from Baltschick are not only much finer, but also somewhat 

 different on the ventral side. It may be found necessary to rename 

 this more robust form, in which case it could be called Amphora 

 interrupta, new species. 



AMPHORA LUNARIS, new species 



Plate 4, fig. 5 



Valve lunate, the dorsal side a strongly convex arc, the ventral 

 strongly concave except for a slight convexity at the middle; ends 

 narrow, rounded, barely swollen; rhaphe adjacent to the ventral edge 

 except toward the ends; its two terminal beads touching the margin 

 of the ends; markings of closely set transverse rows of elongated 

 beads, so spaced as to form a tessellated pattern. 



Length 0.158; width 0.050; lines 5 in 0.01 mm., measured on the 

 dorsal side. 



Resembles slightly A. virgata Ostrup (Ostrup, Diat., N. E. Groen- 

 land, pi. 13, fig. 12). 



Type.— Cat. No. 43577, U.S.N.M. 



