1913. ] S. Kemp: Crustacea Stomatopoda of the Indo-Pacific Region. 163 
breadth is usually not more than 18°5 ; the majority of the specimens were specially 
selected because they appeared broader than was customary. 
Along with this character is correlated a difference in the dactylus of the raptorial 
claw. In G. chiragra the slender terminal portion is long and its apex is always very 
definitely inturned. In the var. platysoma, however, the finger is much shorter and is 
not, or is only very slightly, bent at the tip. 
In the form of the telson all the specimens of var. p/atysoma correspond very closely 
with the individuals to which Lanchester gave the name of acutus (1903, pl. xxiii, fig. 3). 
The keels on the dorsal surface are narrow and the median one is not anchor-shaped and 
does not terminate in a spine ; the lateral marginal teeth are entirely absent. Lan- 
chester’s examples are perhaps identical with those named by Wood-Mason ; but the 
point cannot be definitely settled, for the former author does not mention the other 
characters that separate platysoma from typical chivagra. It is rather remarkable 
that, among normal G. chiragra in the Indian Museum, no specimen occurs with this 
type of telson, whereas all the examples of the var. platysoma from three widely distant 
localities, agree in possessing it. It seems possible, therefore, that this feature is 
correlated with the other characters of the variety; but the variation in the telson is 
so great among typical G. chiragra that it would be astonishing if the form proved 
constant in a large series of specimens. 
The six examples retain but little trace of their original colour, but in four that are 
better preserved than the rest there is a pair of conspicuous round black spots, placed 
close together in the middle of the first abdominal somite. These spots seem only to 
occur very rarely in typical G. chivagra and perhaps constitute a special feature of the 
variety. 
The specimens are registered as follows :— 
ae Port Blair, Andamans. G. H. Booley. 2¢19,77—80 mm. TYPES. 
ses Society Is. Otago Museum. 19,75 mm. 
“2 Mauritius. Purchased. 29, 48°5 and 70 mm. 
The examples which Lanchester recorded as G. chiragra var. acutus were taken at 
Minikoi, and those which Lenz attributed to the same form were found at Zanzibar and 
Madagascar. 
2. Gonodactylus acutirostris, de Man. 
1898. Gonodactylus chiragra vat. acuttrostris, de Man, Zool. Jahrb. Syst., X, p. 695, pl. xxxviil, 
figs. 77), c. 
1899. Gonodactylus chiragra vat. acutirostris, Borradaile, in Willey’s Zool. Results, p. 400. 
1903. Gonodactylus chiragra vat. acutirostris, Lanchester, Faun. and Geog. Maldives and Laccadives, 
I, p. 454. 
1907. Gonodactylus acutirostris, Borradaile, Trans. Linn. Soc. Zool. (2), XII, p. 210. 
This species, known from a single specimen only, may perhaps prove to be merely 
an abnormal example of G. chiragra; it is distinguished by the following features :-— 
1. The anterolateral angles of the rostrum are acute: distinctly sharper than in 
G. chiragra. 
2. The customary pair of tubercles near the anterior margin of the telson are 
