12 NOTES ON CHAT.CIDI.K. 



Thus, the distinctive characters of two species of Eurytoma acquired 

 by cumulative modification since the time of their extinct ancestor 

 are indicative of a comparatively recent epoch ; the difference between 

 Eurytoma and Decatoma shows an earlier time; the wider difference 

 between Eurytoma and Isosoma recalls a still earlier time ; and the 

 remote affinity of Axima and of Aiolomorphus to the other 

 Eurytornidae signifies very distant ages. Axima spinifrons, the only 

 species of that genus, inhabits South America, and has a very broad 

 head, a front with two spiues, very prominent eyes, and a short 

 cubitus, like that of the Chalcididae and of the Torymidse. 



Genus AIOLOMORPHUS. 



Mas. Corpus gracile, convexum, subtiliter punctatum. Caput 

 breve, transversum, thoraci oequilatuui ; frons erecta. Oculi para, 

 subprominuli. Palpi breves. Autenme longae, graciles ; flagelli 

 articuli longissimi, setulosi. Prothorax magnus, subquadratus. Meso- 

 thorax breviusculus ; parapsidum suturas bene deterniiuatae. Meta- 

 thorax longiusculus, subdeclivis. Petiolus longus, gracilis, punctatus. 

 Abdomen glabrum, clavatum, subcorapressum. Pedes graciles; 

 tibiarum calcaria brevissima ; tarsi 5-articulati. 



Male. Boity slender, convex. Head and thorax finely punctured. 

 Head short, transverse, as broad as the thorax ; front erect. Eyes 

 small, slightly prominent. Mandibles small. Palpi short. Antennae 

 filiform, slender, pubescent, seated in the middle of the front, longer 

 than the thorax, mutilated in the specimen described ; first joint 

 long ; second short ; third, fourth and fifth very long, thickly beset 

 with short bristles on each side. Thorax thickly and minutely 

 punctured. Prothorax large, subquadrate. Mesothorax rather short; 

 sutures of the parapsides strongly marked ; scutellum rather small. 

 Metathorax elongate, slightly decumbent. Petiole slender, punctured, 

 as long as the hind coxa?. Abdomen smooth, shining, clavate, slightly 

 compressed, a little longer than the thorax exclusive of the petiole. 

 Legs slender, moderately long; tibiae with very short apical spurs; 

 tarsi 5-jointed ; joints from the first to the fourth successively 

 decreasing in length. Wings moderately long and broad ; ulna 

 about one-third of the length of the humerus ; radius much shorter 

 than the ulna, longer than the cubitus ; stigma small ; spurious veins 

 such as the brachial and the cubital well-defined. 



This genus has a remarkable structure. In the development of the 

 spurious wing-veins it differs from all the other Chalcidiae, with the 

 exception of the Leucospiche and of some genera that appear to be 

 related both to the Cbalcidiffi and to the Cynips tribe. It has very 

 little affinity to the Leucospidee and to the Chalcididae ; it is nearer 



