40 FORAMINIFERA OF THE CRAG. 
Characters.—Shell ovato-globose or pear-shaped, usually Entosolenian. Surface 
covered with an ornamentation of elevated ridges, forming a network with hexagonal 
or sub-hexagonal meshes. Colour white to yellowish. Length ;,th or less to 3th inch. 
This represents a state of ornamentation peculiar to the Zagere amongst the “hyaline,” 
and to certain varieties of Miliola seminulum among the “porcellanous” Foraminifera. 
In L. Melo the cross-bars are often weaker than the longitudinal ribs, and pass straight 
across from rib to rib, like the secondary veins in a monocotyledonous leaf, such as 
Alisma, Myrsiphylium, &e. In L. squamosa, however, not only have the secondary riblets 
become equal to the primary, but, by the zigzag inflection of the latter, a nearly regular 
hexagonally areolated ornament is produced, reminding one strongly of the polygonal 
meshes produced by the more perfect reticulation of the woody skeleton of a dicotyledonous 
leaf. Early observers, using but imperfect microscopes, compared this retose ornament 
with a scaly skin of a fish (see Williamson, ‘Monograph,’ p. 12), and, indeed, from young 
and small specimens, mounted in Canada balsam and viewed as transparent objects, it 
would be almost impossible, even with the best instruments, to contradict such a 
diagnosis. 
Professor Reuss, in his ‘Memoir on the Lagenide,’ pl. 5, fig. 74, figures, under the 
name of L. geometrica, a very beautiful modification of this variety, in which the ornament 
takes the form of very small, regular, hexagonal meshes, separated by delicately thin 
elevated walls. Professor Williamson’s figure (‘Monogr.,’ pl. 1, fig. 32) of Z. sguamosa, 
var. hexagona, represents a similarly regular marking, but here the ridges are broader, 
and the number of meshes finer. His JZ. sguamosa, var. scalariformis, has the same 
general character, but there is proportionately a smaller amount of ornament, and the 
interstitial spaces are still larger. 
In this reticulate Zagena the neck is usually intussuscepted (Entosolenian) ; but in one 
of the large fossil form (Z. squamoso-tubifera, Parker and Jones, ‘ Phil. Trans.,’ 1865, pl. 18, 
fig. 7), the neck is protruded in some cases to a considerable extent, and has about three 
secondary tubular apertures arising from it laterally, and almost at right angles to the main 
tube. This is an isomorphism with Polymorphina tubulosa, and with certain feeble bifur- 
cating forms of WVodosaria from Cretaceous beds. 
L. squamosa is of world-wide occurrence ; but, like Z. Melo, is not so abundant as the 
long flask-shaped and the marginated forms. In the Arctic Seas it is not uncommon, 
and on our own shores it is found sparingly everywhere. It is found fossil in the Black 
Crag of Antwerp (Reuss), and in the Tertiary clays of North Italy. By far the bulkiest 
specimens of Z. sguamosa that we have seen are from a Tertiary sand, which, rich in many 
varieties of Lagene, in Ovulites, Polymorphina, and Vertebralina, was taken from the 
inside of a Cerithium giganteum from Grignon. A single specimen collected by Mr. H. C. 
Sorby, at Bridlington, kindly placed in our hands with his other specimens from the 
same locality, is the only instance we know of its occurrence in the Pliocene beds of 
Britain. 
