2 
Psyche 
[March 
workers, with heads of similar structure but of different 
sizes. Then Emery, in 1906, discovered in the Baltic amber 
a form which closely resembled the Bornean janeti and 
described it as D. theryi. While reviewing the ants of the 
Baltic amber in 1913 I was able to recognize several speci- 
mens of G. hoernesi and D. theryi and two intermediate forms 
which I described as G. annectens and D. mayri. Two years 
later (1916) I described a winged female from the Island of 
Luzon, in the Philippines as Dimorphomyrmex luzonensis, and 
in 1921 another species, Gesomyrmex howardi, from a couple 
of workers taken by Prof. C. W. Howard near Canton, 
China. These workers I interpreted as major and minor 
workers respectively and noted that the former resembled 
the worker of Dimorphomyrmex. The new species from Java 
now shows that the specimens of howardi are really media 
and minima workers, that those of G. hoernesi and chaperi, 
described by Mayr and Andre are minimse, that those of 
D. janeti are maximse and mediae of G. chaperi, and that the 
workers of D. theryi, D. mayri and G. annectens are in all prob- 
ability the maximae, large mediae and small mediae respec- 
tively of G. hoernesi. This will be clear from the following 
description and figures of the new species brought to light 
by Dr. Kalshoven. 
Gesomyrmex kalshoveni sp. nov. 
Worker maxima. (Fig. 1, a-d) Length 5-6.6 mm. 
Head subrectangular, about 11/4 times as long as broad, 
slightly narrower in front than behind, with the sides dis- 
tinctly concave in front of the middle; the posterior border 
feebly concave, the posterior corners convex and rounded; 
the dorsal and gular surfaces rather flat. Eyes elongate, 
convex, scarcely reniform, with straight or very nearly 
straight internal and impressed posterior orbits, one-third 
as long as the head and well up on its dorsal surface. Ocelli 
minute, unpigmented, the anterior smaller than the two 
posterior, which are on a level with the posterior orbits of 
the eyes. Mandibles stout, convex, with strongly rounded 
external borders, 8-toothed, the first, second, fourth, sixth 
and eighth tooth, counting from the apex, larger than the 
others and rather blunt. Clypeus short and flat, its anterior 
