SCIENTIFIC SUMMARY. 
367 
This "basal zone would seem to represent a sterile and persistent part of the 
androphore, in which at one time the whole conical body was covered with 
a felted layer, composed of the filaments and their appendages, reminding 
one by its position and arrangement of the male flowers of the Reed-mace 
( Typho ). 
The female inflorescence of Williamsonia is furnished with a globular 
envelope like that of the male flowers, but its bracts are a little shorter. The 
organ contained in this envelope, and which is certainly deciduous when 
mature, consisted of a convoluted (F) receptacle of more or less globular 
form. The central leaves of the envelope, which have remained in place, 
testify by their thickness and leathery texture to the primitive nature of 
this formation. In their midst stands the globular conceptacle, the upper 
parts of which are covered with carpellary areas ; and in the lower part of 
the receptacle we see the fibrous, woody tissue of which the axis was 
composed. 
The remains of the genus Goniolina, D’Orbigny, appear as ovate bodies, in 
the form of cones rounded at the upper end, and borne upon a cylindrical 
stalk. The surface is covered with very regular hexagonal areas, arranged 
in spiral lines. The areas are smaller towards the point of insertion of the 
stalk. These fossils were formerly regarded as Echinoderms, and described 
as Crinoids under the name of Goniolina geometrica. ( Comptes Mendus, May 
23 and 30, 1881 ; Kosmos, 1881, Vol. IX.) 
Trilobites. —Some ten years since Mr. Billing and Dr. Henry Woodward 
announced the discovery of jointed limbs in a species of Asaphus, and Mr. 
C. D. Walcott has since devoted much careful labour to the investigation of 
the structure of another Trilobite, Calymene senaria, of which he was able 
to obtain a great quantity, in a wonderful state of preservation, from a part 
of the Trenton Limestone. By cutting thin sections of these Mr. Wallcott 
has been able to demonstrate the existence in them of regular walking feet, 
and also to ascertain the number and character of all the limbs, so as to 
reconstruct the lower surface of the animal. It appears that the Trilobites, 
from the absence of antennae, and the nature of the anterior pairs of limbs, 
belong to the class Pcecilopoda, now represented only by the King-crabs, but 
that they form a distinct group in the class. They differ from the extinct 
Eurypterida, as also from the Xiphosura (King-crabs), living and fossil, by 
the possession of four pairs of walking feet surrounding the mouth, and also 
by the presence on each thoracic and abdominal segment of a pair of walking 
feet, furnished with branchial appendages. 
MINERALOGY. 
Characters of some important Minerals . — The results obtained by the 
more exact methods of investigation employed in Mineralogy of late years 
have led to the change of a considerable number of minerals to systems of a 
lower grade of symmetry than those to which they had previously been 
