FAMILY SPHH#ROMIDA. 115 
acute in the male, rather obtuse in the female. Urp. with 
both rami long, in the female sub-equal in length, in the male 
exp. is elongate, considerably longer than endp. Male with 
appendix masculina on endp. of plp.? 
(12) Tecticeps (Richardson). 
VII. Nores on THE GENERA AND THEIR SPRCIES. 
The genera are here dealt with in the same consecutive 
order asin the preceding chapter. As to the enumeration of 
the species I refer to the ‘‘ Introductory Remarks.” 
Sub-family Limnoriine. 
Limnoria (Leach).—The type is L. lignorum (Rathke). 
On the three other species known see Stebbing in ‘ Fauna 
Maldive and Laccadive Archip.,’ vol. ii, p. 714. 
Sub-family Plakarthriine. 
Plakarthrium (Chilt.)—The type is P. typicum (Chilt.) 
Whether P. (Chelonidium) punctatissimum (Pfeff.) be a 
closely allied species or only a synonym I am unable to 
decide. Pfeffer published (1887) a very detailed, and as a 
whole useful account of his form, but some of his anatomical 
statements and morphological interpretations are incorrect, 
and his opinion on the systematic position of the genus is 
without foundation.! 
Sub-family Spheromine. 
A. Spheromine hemibranchiate. 
(1) Spheroma (Bosc).—To the characters given above it. 
may be added that in all species the end of abdomen, even if 
moderately narrow, is really rounded, not triangular or 
subacute ; its marginal part, seen from below, shows scarcely 
any trace of a longitudinal mesial excavation, not to speak of 
a longitudinal groove as in Isocladus. According to my 
own examination the following species belong to this genus: 
1 Pfeffer establishes it as the type for a new family, and adds “ Die Fa mili 
scheint mit den Onisciden am nichsten verwandt.” 
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