NO. 6 
DFXAPOD AND OTHER CRUSTACEA — SCHMITT 
21 
swimming pair, of legs is smooth, not armed with spimiles. T. cxetas- 
iica and most of its subspecies and varieties are also distinguished 
from our species by the al)sence of these propodal spinules which are, 
however, present in at least one variety of cxetastica. All the exetastica 
forms differ from T, roosevelti and most if not all other Thalamitas 
in possessing a small accessory tooth or spine on the outer side of 
the first lateral, extraorbital tooth of the carapace. There is no trace 
of such an accessory tooth in T. roosevelti. 
The basal antennal joint in our species is not wholly smooth, as it 
has been described for T. aleocki, or low and almost indistinguishable, 
as in imparinianus ; neither is the crest what one would in any sense 
call denticulated, which it plainly is in T. investigatoris, exetastica, 
gardineri, and kiikenthali, or armed with two large and prominent 
teeth fused at the base as in T. tennipes. In T. roosevelti the basal 
joint, as described above, has a well-formed high crest visilile in dor- 
sal view, rather smooth appearing and at most no more than obscurely 
denticulated, revealing, under the magnifier, small, low, irregularly 
placed swellings or obsolescent small tubercles. 
With respect to the character of the basal joint and the armature of 
its hands, T. roosevelti stands near T. aleocki; in the equality of the 
chelipeds, proportions and general appearance of the front, carapace, 
and lateral teeth, near T. gardineri. From the former our species 
differs in having a relatively .wider and deeper incision or sinus be- 
tween the median lolies of the front, in having the fingers longer 
instead of shorter than the palmar portion of the hand, and in being 
armed with nearly twice as many or more than twice as many spinules 
on the hinder margin of the propodus of the last pair of legs. From 
T. gardineri our species differs by virtue of the fact that the sulimedian 
lobes of the front overlap the median lobes in not having a truly or 
plainly denticulated crest on the basal antennal joint, and in the rela- 
tively longer fingers. 
Even if Miss Gordon’s recently described T. malaccensis (Bull. 
Raffles Mus., No. 14, p. 176, figs. 2, 3, 1938) is to be considered one 
of the species possessing a six-lobed front, the fact that the outer 
lobes of the front are marked off from the submedian lobes by a mere 
convexity of the anterior margin instead of a well-marked sinus or 
incision sets it well apart from the one we have here described. 
Platypodia rotundata (Stimpson) 2J' 25 
Actea dovii Stimpson ij 
Actea sulcata Stimpson : i? 
Mieropanope xantiisii (Stimpson) ij' 4$ (3 ovig.) 5 juw 
