The Ants of the Baltic Amber. 
109 
Gcesomyrmex hörnesii Dalla Toure, Catalog. Hymen. VII, 1893, p. 176. 
Gesomyrmex hörnesi Ern. Andre, Bull. Soc. Zool. France, XX, 1895, p. 82; Hand- 
lirsch, Foss. Insekt. 1908 p. 859. 
Work er. Length 2,5 — 6 mm. 
Body slender. Head, excluding the mandibles, a little longer 
than broad, as narrow behind as in front, with distinct bnt rounded 
posterior corners and straight or feebly excised posterior border, very 
short cheeks and convex vertex. The head is broadest through the 
eyes, which are even larger, more convex and more reniform than 
in G. annectens, being more than half as long as the head and more 
approximated anteriorly. They project beyond the lateral borders of 
the head when it is seen directly from below. Ocelli minnte. Frontal 
area and frontal groove obsolete. Clypens fully as long as broad, 
anteriorly projecting as a long, rather narrowly ronnded lobe over 
the bases of the mandibles. The surface of the clypens is convex 
posteriorly but its projecting border is flattened or slightly concave. 
Mandibles very long, decussating when closed, with 9 long, acute 
teeth, some of which are slightly shorter than others. The outer 
borders of the blades are straight at the base, then feebly concave 
just behind the convex tips which are bent downward. The basal 
border is nearly as long as the apical, the mandible being broadest 
where the two borders meet, although its breadth at this point is not 
more than a fifth of 
its total length. Palpi 
and antennm more 
slender than in G. 
annectens , the scapes, 
which are somewhat 
incrassated at their 
tips reaching a little 
beyond the middle Fig 53 . Gesomyrmex hoernesi Mayr. Worker, B 18396. 
of the eyes ; all the 
funicular joints longer than broad. Thorax very similar to that of 
G. annectens but more slender, the mesonotum longer and passing 
into the metanotum somewhat less abruptly. Petiole as long as broad, 
its node low, a little more than twice as broad as long, compressed 
anteroposteriorly, rounded and blunt above, with convex anterior and 
posterior surfaces. Gaster elongate elliptical with a circlet of coarse 
anal cilia. Legs rather slender. 
Sculpture, pilosity and coloration as in G. annectens, the longitudinal 
striation of the mandibles, cheeks, clypeus and front, however, more delicate. 
