256 



WHEELER. 



figures a series of transverse sections through its anterior and posterior 

 portion. The accompanying sketches (Figs. 1 and 2) represent the 

 organ in L. nigriventris and unicolor. In both species it is hard and of 

 a glassy texture, as Emery observed, and its four valves (v.) are large, 

 with rounded, lobe-like, anterior ends. Their inner surfaces appear 

 to be very hairy, especially along the edges. The bulbous, posterior 

 portion (b.) of the organ is large and rather sharply marked off from 

 the valvular and cylindrical regions (c). The muscular layer (m.), 

 which seems not to have been seen by Emery, is well-developed. 



Fig. 1 Fig. 2 



Figure 1. Proventriculus of Leptomyrmex nigriventris, i. wall of crop, 

 V. valve, m. muscles, b. bulb, c. cylindrical portion. 



Figure 2. Preventriculus of Leptomyrmex unicolor. v. valve, ?/i. muscles, 

 h. bulb, c. cylindrical portion. 



especially in yiigriventris. In unicolor this layer is much feebler and 

 the whole organ is shorter and smaller. 



No other Dolichoderine ant has a proventriculus of the same type 

 as that of Leptomyrmex, though in Dolichoderus it is somewhat similar. 

 Since the proventriculus functions as a valve between the ingluvies, 

 or crop and the ventriculus, or true stomach, its very high development 

 in the species of Leptomyrmex, as shown by the large size of the chiti- 

 nous valves and the thick layer of musculature enveloping them, is 

 evidently correlated with the habit in these insects of storing large 

 quantities of liquid food in the crop. This is also indicated by the 



