Review of Recent Geological Literature. 335 
omy by W. D. Matthew, noticed in the September number of the 
Geologist, the other on the primitive stages of some highly specialized 
forms, Aeidaspis and PhaMhonides. All embryonic stages that had 
already been described by Barrande, Ford, Walcott and Matthew were 
of early and less complicated types. The larva of Aeidaspis i . I. tuber 
culala Conrad) has a predominating cephalon. no thoracic segments, 
and a small, obscurely separated pygidium. That of PhaMhonides has 
about equal development of cephalon and pygidium, but the thorax is 
also undifferentiated. Compared with Barrande's earliest stage of Sao, 
in which neither thorax nor pygidium i6 separated, these forms would 
seem to be derived or secondary. A remarkable feature in both is the 
presence of conspicuous surface spines, which cover the cephalic and 
pygidial margins in Aeidaspis but are not marginal in i PhaSthonides ex- 
cept on the pygidium, while several longitudinal rows extend over the 
entire test. These features are shown to be specific characters whose 
presence upon the larval test indicates the action of the law of earlier 
inheritance. In some concluding remarks the author infers that these 
early larvas in which the distinction between cephalon and pygidium is 
obscure or wanting are comparable to the nauplius of the Crustacea. 
It is also suggested that the earlier segmented stages of those forms 
resembled immature conditions of certain of the Isopods. The investi- 
gations of Matthew, jr., have also indicated that in the nature of their 
appendages the trilobites approach the Isopods, the latest evidence thus 
tending to confirm the idea of Dean Buckland of over a half century 
ago. 
Materialen zur Kenntniss der Devonischen Fauna des Altafs; byTH. 
Tschernyschew. (pp. 140, pis. i-iii, 1893.) 
A group of about twenty species from the limestones of the Krju- 
kowsk mine in the southwestern Altai indicates a lower Devonian 
fauna. One of the most characteristic forms is a large Phacops (P. 
altaicus) similar to the P. bombifrons and P. logani Hall, of the Ameri- 
can lower Devonian, but without the duplicate pygidial ribs of those 
species. Species of Bronteus, Harpes, Proetus, Goniatites latiseptatus, 
etc., afford a correlation with the European lower Devonian. 
Protospongia rlienana; by Clemens Schlutek. (Zeitschr. der 
deutsch. geolog. Gesellsch. Jahrg. 1892, pp. 615-618.) 
To this genus the author refers a hexactinellid sponge from the lower 
Devonian Hunsnick roofing-slates, at (Jemunden. Protospongia has 
not before been reported from faunas later than Cambrian or earliest 
Silurian (Ordovician), and there are some considerations, notably the 
large size and coarse reticulation, which ally this fossil more nearly 
with members of the genera Dictyospongia, Ectenodictya, etc. 
On Palaeosaccus Dawsoni Hinde. .1 new genus and species of Heir 
actinellid Sponge from the Quebec Group ^Ordovician) at Little M6tis, 
Quebec, Canada; by G. J. Hindi;. (Geological Magazine, 111, x, pp. 56- 
58, pi. iv, 18915.) 
