404. Dr. H. Woodward—On a Fossil Schizopod Crustacean. 
that these represent the marsupium of the Mysidacea. But Sars 
has pointed out that the ‘ovisacs’ are apparently formed by the 
consolidation of some cementing substance which is extruded along 
with the eggs from the oviducts.”’ 
Beneath I have given the classification proposed by Dr. W. T. 
Calman for Crustacea of the sub-class Malacostraca :— 
Series Leptostraca, Claus, 1880. 
Division PHYLLOCARIDA, Packard, 1879. 
Order NEBALIACEA, noy. nom. 
Series Eumalacostraca, Grobben, 1892. 
Division SYNCARIDA, Packard, 1886. 
Order ANASPIDACEA, NOY. nom. 
Division PERACARIDA, nov. nom. 
Orders MysiDAcEA. 
CuUMACEA. 
TANAIDACEA. 
IsoPopa. 
AMPHIPODA. 
Division EUCARIDA, nov. nom. 
Orders EUPHAUSIACEA. 
DEcAPODA. 
Division HOPLOCARIDA, noy. nom. 
Order STOMATOPODA. 
Dr. Calman gives the following diagnosis of his proposed division 
Peracarida :— Carapace, when present, leaving at least four of the 
thoracic somites distinct. First thoracic somite always fused with 
the head. Antennal protopodite typically of three segments. 
Mandible with lacinia mobilis (except in parasitic and other modified 
forms). Thoracic limbs flexed between fifth and sixth segments. 
‘Oostegites’ attached to some or all of the thoracic limbs in female, 
forming a brood-pouch. No appendix interna on pleopods. Hepatic 
ceca few and simple. Heart elongated, extending through the 
greater part of the thoracic region, or displaced into abdomen. 
Spermatozoa filiform. Development taking place within the brood- 
pouch ; young set free at a late stage.” (Ann. & Mag. Nat. Hist., 
ser. VII, vol. xiii (1904), pp. 156, 157.) 
The following may serve as illustrations of the frequent occurrence 
and variation in form of the brood-pouch in living Crustacea of 
different orders included in Dr. Calman’s division Peracarida. 
In the family Lophogastride (see the Rev. T. R. R. Stebbing’s 
History of Recent Crustacea, 1893, p. 256) the marsupium consists of 
seven pairs of plates, the young undergoing their metamorphosis 
within the egg. The same arrangement occurs in the Eucopiide 
(op. cit., p. 260). 
In the Myside the marsupium is composed of seven, or more often 
of only two or three, pairs of plates (op. cit., p. 267). 
In the Cymothoide the female has five pairs of marsupial plates on 
the first five pairs of thoracic limbs, and small supplementary plates 
on the last two -pairs (op. cit., p. 889). In this family the plates of 
