202 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
epistome; the body-cavity, on the other hand, contains a pair of renal 
organs and the generative organs. The renal organs of both Phoronis 
and the Bryozoa agree in being short, ciliated tubes, with a retro- 
peritoneal course, which are, on the one hand, connected with the body- 
cavity by an infundibular oritice, placed anally of the oesophagus, and 
open to the exterior by an outer pore. 
With regard to the differences between the Bryozoa and Phoronis, 
the phylactolaematous division of the former has lophophoral arms ; to 
this statement, however, Fredericella is an exception. Another difference, 
which appears to be important, is the absence of a blood-vascular system 
in the Bryozoa. This, however, may not be significant, as its absence 
is probably due to loss during phylogenetic development. In a young 
Phoronis the difference in the arrangement of the mesenteries is less 
unlike what obtains in Bryozoa than is the case with the adult. 
Although the author points out the resemblances between Phoronis and 
the Bryozoa, he does not go so far as those who regard the former as 
merely an aberrant Bryozoon ; his object is merely to point out the 
genetic relations which appear to obtain between these two classes of 
animals. 
Echinodermata. 
Morphology of Bilateral Ciliated Bands of Echinoderm Larvae.*— 
Dr. B. Semon is of opinion that the dipleural larvae and Tomaria offer 
well-marked differences from the ciliated larvae of higher and lower 
Worms, as well as of Molluscs. It would seem, therefore, impossible to 
homologize the circumoral ciliated band of Echinoderm-larvae with the 
ciliated apparatus of other larval types. The structures have probably 
been acquired independently. 
To make our judgment satisfactory we require, however, a better 
knowledge of the larval nervous systems than we have at present ; it is 
certain that so highly differentiated a larva as Bipinnaria, with its rich 
and complicated muscular apparatus, must have a well-developed and, 
relatively speaking, highly developed nervous system. And of this we 
yet know but little. 
Calamocrinus Diomedae.j' — Prof. A. Agassiz has a preliminary note 
on a new stalked Crinoid from the Galapagos. At first sight this new 
form might readily pass as a living representative of the fossil 
Apiocrinus, but it has also points of resemblance to Millericrinus, 
Hyocrinus, Bhizocrinus. Like these lust, it has only five arms, but 
these are not simple, but send off from the main stem of the arm three 
branches to one side and two to the other. The system of interradial 
plates is highly developed, as in Apiocrinus and Miller? crinus, six rows 
of solid polygonal imperforate plates being closely joined together, and 
uniting the arms into a stiff calyx as far as the sixth or seventh radial. 
These solid plates extend over the prominent anal proboscis ; the oral 
plates are small. The stem is somewhat curved at the upper extremity ; 
it tapers very gradually, and in its general appearance recalls that of 
Apiocrinus ; it is cylindrical and has no cirri. There are five distinct 
basals in one specimen, in another the sutures can be recognized, and 
* Jenaische Zeitschr. f. Naturwiss , xxv. (1890) pp. 16-25 (1 pi.). 
+ Bull. Mus. Comp. Zool., xx. (1890) pp. 165-7. 
