194 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Deep-sea Asteroidea from the Indian Ocean.* — Dr. A. Alcock gives 
details of the deep-sea starfishes obtained by H.M. Indian Marine Survey 
steamer ‘ Investigator/ of some of which he has already published pre- 
liminary notes. The enclosed basin of the Andaman Sea in its 
moderate depths appears to be peculiarly favourable to starfish life ; the 
calcareous sand and ooze which accumulates between 200 and 300 
fathoms seems to afford to Asteroids, as to Ophiuroids and Echinoids, an 
optimum of development, for there is not only abundance, but also 
variety. The author has amended the diagnoses of Persephonaster and 
Dictyaster , has redescribed five species, and now gives descriptions of 
three species of Brisinga, which before were merely named. In addition 
to various “ new species ” there are as new genera Dipsacaster, an Astro- 
pectinid with no arms, and Milteliphaster , which is allied to Calliaster, 
and is most remarkable for the spines on the lower surface, which end 
in swollen bifid or multifid spines, and recall the long spines of certain 
Cidaroids. 
Organogeny of Amphiura squamata.t — Mr. T. W. MacBride makes 
a short reply to the recent criticism of M. Cuenot, urging that in one 
case he has misinterpreted the facts, and in another merely made a guess. 
As to the small size of Amphiura squamata unfitting it for study, it is 
on this very account favourable, since the preserving fluids penetrate 
more rapidly and thoroughly than they do in larger forms. 
Movements of a Tropical Ophiurid.^ — Dr. C. P. Sluiter describes 
the swimming movements of a species of Ophioglypha, which he observed 
in his aquarium at Java. It is common at Batavia, where it lives in 
depths of from 4 to 15 fathoms, and ordinarily creeps about the bottom. 
'When some new animals were put into the tank the small Ophioglypha 
began to make powerful rhythmic movements with its arms. The 
movement was always so effected that one arm was directed straight 
backwards and remained immovable, while the other four made powerful 
backward strokes, then moved slowly forwards, and again made powerful 
back strokes. It does not appear to matter which arm is used as the 
rudder. It is clear that this mode of swimming must be quite different 
from that adopted by Opliiopteron where the long arm-spines are connected 
together by a thin membrane. 
Formation of Skeletal Parts in Echinoderms.§ — Herr C. Chun has 
made some observations on the spicules of an Auricularian type of larva 
which he obtained at the Canary Islands. He finds that, while the 
skeletal parts of Echinoderms have been regarded as essentially inter- 
cellular structures, the forms of the deposits are stretched out within a 
multinuclear cell by an organic membrane which forms complicated folds, 
and that in this circumscribed form the hard parts are moulded. 
Ccelentera. 
East African Coral Reefs. ||— Dr. A. Ortmann describes the coral 
reefs of Dar-es-Salaam and adjacent regions, which he studied with 
* Arm. and Mag. Nat. Hist., xi. (1893) pp. 73-121 (3 pis.). 
f Zool. Anzeig., xv. (1892) pp. 449-51. 
X Tijdschr. Nederl. Dierk. Yereen., iii. (1892) pp. 181-3. 
§ Zool. Anzeig., xv. (1892) pp. 470-4. 
1| Zool. Jahrb., vi. (1892) pp. G31-70 (1 ph, 2 figs.). 
