LESQUEREUSIA. 65 



Genus 20. LESCiUEREUSIA* Schlumberger, 1845. 



Difflugia (pars) LECLERC in Mem. du Mus. II (1815), p. 477. 

 Lecquereusia SCHLUMBERGER in Ann. Sci. nat., Zool. (3) III 

 (1845), p. 255. 



Test compressed, ovoid or globose in side view, 

 narrowed at the neck ; the latter unsymmetrical and 

 so joined to the body as to give the structure more or 

 less the appearance of a semi-spiral, or it may be 

 tangentially posed with a slight curve. The test, 



74 73 



FIG. 73. " Lesquereusia spiralis'' Ehrenb. (? truly L.jurassicaSchlumb.). 

 FIG. 74. " L. modesta" Rhumbl. (? truly L. spiralis Ehrenb.). Both 

 from Dunham Marsh, Cheshire, x about 250. 



both neck and body, composed of transparent chitinous 

 membrane with an interlacing pattern of minute curved 

 or comma-shaped rods, or (in one species) incrusted 

 with sand-grains, and opaque. The internal cavity 

 only partially filled by the plasma ; a stream of ecto- 

 plasm from the main body traversing the neck, and 

 reaching the orifice through an aperture formed by 

 the constriction. 



[The names Lesquereusia spiralis and L. modesta 

 are here retained for the two following species 

 with much doubt, for they appear to have been mis- 



* [Dr. Penard has pointed out that the genus was named after the Swiss 

 naturalist Lesquereux, this therefore being the correct spelling.] 

 VOL. II. 5 



