58 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Development of External Features of Branchipus grubei. — 
Alfred Oehmichen ( Zool . Anzeig ., 1921, 53, 241-5,1, 18 figs.). The 
first five stages are described, with particular reference to the antennae, 
the mouth-parts, and the limbs. J. A. T. 
Symbiosis of Isopods and Hydroids. — E. Stechow (Zool. Anzeig ., 
1921, 53, 221-8, 1 fig.). Symbiosis between Brachyura and Hydroids 
has been recorded in many cases, but it is rare between Isopods and 
Hydroids. Stechow reports the luxuriant growth of Obelia geniculata 
on the posterior half of Anilocra physodes in the Mediterranean, and the 
occurrence of Obelia long a sp. n. on the posterior dorsal surface of 
Serolis zoiphila from Kerguelen. There does not seem to be any 
masking of the Isopod, as the growth is confined to the posterior regions. 
The Hydroids may profit by being carried about and by getting particles 
from the Crustacean’s repasts. J. A. T. 
Fresh-water Crab in Tasmania. — Chas. Chilton ( Proc . Roy. Soc. 
Tasmania , 1919, 93-5). The small crab Rymenosoma lacustris Chilton 
was originally described from near Auckland, New Zealand, and has 
since been recorded from other localities in New Zealand, also from 
Norfolk Island, Lord Howe Island, and from two localities in Victoria. 
Its occurrence, now reported, in Tasmania is additional evidence of its 
wide distribution and of its antiquity. There are some peculiarities in 
the Tasmanian specimens, but not marked or constant enough to justify 
their separation. J. A. T. 
Blood-cells of Astacus. — B. Nold (Zool. Anzeig., 1921, 52, 277- 
85, 7 figs.). The blood of Astacus fluviatilis includes amoebocytes and 
trophocytes — both colourless. The former are in a great majority. 
Most of the trophocytes migrate into the tissues. In Molluscs the 
trophocytes are restricted to the tissues. The amoebocytes show active 
movements, with pointed hyaline pseudopodia which sometimes form 
anastomoses. It seems probable that a spherical shape is assumed when 
the amoebocytes are not in small arteries and capillaries with a slowed 
flow of the blood. The minute structure of the amoebocytes is described. 
A nucleus may occasionally show a median constriction, but it does not 
seem likely that division ordinarily occurs in the blood. The tropho- 
cytes are derivable from young amoebocytes. The protoplasm increases, 
mitochondrial secretion granules appear around the nucleus, and in the 
vicinity of the granules there arise nutritive trophoplasts which break 
up and make the protoplasm very vacuolate as they disappear. The 
trophocytes retain the phagocytic capacity of the amoebocytes. 
J. A. T. 
Development of Panulirus japonicus. — Arato Terao (Rep. Imp. 
Fisheries Inst. Tokio, 1919, 14, 1-7, 4 pis.). The egg-fixing cement 
seems to be due to the tegumental glands of the swimmerets of the female. 
The cells from the blastopore migrate en masse into the yolk, becoming 
a dome-shaped syncytium. In the intermediate areas between the 
appendages of the egg-nauplius there are lateral or inter-appendicular 
growth-stripes. There are three unpaired dorsal organs, which may be 
interpreted as embryonic moulting-glands. The longitudinal contraction 
