LCfTUSIA FROM DRIIISH COLUMBIA. 71 



mental character of the test of Loftmia is apparent even unde • a 

 low power, and it has a peculiar sparkling as]tect. 



In form, the species bears a close resemblance to L. pcrsica, espe- 

 cially to the stouter variety represented in plate Ixxvii. fig. 3 

 of iiossi-8. Carpenter and lirady's memoir. I have not observed any 

 specimens to assume a form quite so mitch elongated in proportion 

 to the breadth as that given in figure 3 of the same plate. It is a 

 regular oval, with circular cross section, the ends varying from ob- 

 tusely rounded to bluntly spindle-shaped. The Marble-Canon form, 

 however, is very much smaller than L. persica, both in its external 

 dimensions and proportiv;nally in all its structures. By measure- 

 ment of a number of specimens, the average length of the shorter 

 axis appears to be from 10 to 20 hundredths of an inch, that of tho 

 longer axis about 30 hundredths ; one specimen measuring as much 

 as ^y^- in its lesser diameter has been found. Some may attain a 

 lengtli of y'mj or even j^^~ of an inch ; a remarkably long and nar- 

 no-w exiimplo measured j^'j of an inch by yt,'^t o*: ^'i inch. I have 

 not been able to observe any regular furrowing of the outer surface 

 of the test, though from the appearance in cross sections, it is pro- 

 bable that a tendency to such marking exists in some specimens. 

 Others must have l)ecome more or less rough and irregular in form, 

 from the acervuline mode of growth fre(|uently assumed in the larger 

 examples. !Maiiy specimens are, like those of the Persian form, more 

 or less oval or elliptical in the outline of tho cross section. As, how- 

 ever, in some specimens many exam])les may be found in different 

 stages of degradation towards absolute shapelessness, I believe, as 

 Sir. Brady does of the Persian form*, that this is abnormal, and the 

 result of changes after the dcatli of the animal. In some cases, spe- 

 cimens of irregular form are scattered among others of normal ap- 

 peal nee, and seem to have decayed or collapsed more or less com- 

 pletL _, before the consolidation of the sediment, in otlier layers, 

 the -whole rock has very evidently been compressed during metamor- 

 phism, all the Eoraminifera being flattened parallel to one plane. 



The structure of this form is in most respects strikingly similar 

 to that of Lnffii.tia prrsica, and, like it, extremely complicated. With- 

 out Mr. Brady's elaborate and lucid description of tho former, it 

 would have been a matter of no small difficulty to make out tlie plan 

 of growth of this smaller species, which it is possible to examine in 

 thin sections only. 



In describing the structure, tho same terms made use of in the 

 memoir already severnl times referred to will be employed. I would 

 also call attention to the diagrammatic representation of the plan of 

 the test of Loftn.sid on page 743 of the memoir. 



No central primordl.il chamber, or se^-ics of chambers, like that of 

 Parheria has been found. The nucleus of the test appears to be, as 

 in L. perska., a loose-textured granulated mass, nearly circular in 

 cross section. It has not been observed, however, to become so di- 

 stinctly cancellated as appears to be the case in L, persica. 



In theory, this test may be said to consist, like that of tho original 



* Op. cif. p. 742, 



