1952 i Eisner and Wilson — Formicine Proventriculus 59 
phorini, Plagiolepidini, and Myrmelachistini) , the occlusory 
tract is a prominent dome which surmounts the bulb. It is 
traversed by the same cruciform slit found in the euform- 
icines. Anteriorly the slit is covered by dense chitinous 
hairs ; this area is exactly comparable, if not homologous, 
to the filtered slits of the euformicine calyx and tract. 
Posteriorly the slit is devoid of hairs, and the tips of its 
arms broaden into canals which open into the bulb canals, 
again very much as in the euformicines. The proven- 
triculus characterising Emery’s section Heteroformicinae 
(Myrmecorhynchini and Myrmoteratini) appear from 
Emery’s figures to be essentially similar to the alloform- 
icine type, and there seems to be little justification for 
considering them other than aberrant alloformicines. The 
advanced dolichoderine type of proventriculus (Tapino- 
mini) is the most complicated and difficult to understand, 
but in essential details it is still similar to the alloformicine 
type. There is an anterior filter area and posterior canals. 
Sepals, or sepal-like structures, are present and reflexed 
back over the bulb, with which they fuse. The chitinous 
septa produced by the fusion of the bulb and inverted 
sepals serve as the points of attachment of the bulb musc- 
ularis. The proventriculus of the myrmicine tribe Cepha- 
lotini has unquestionably evolved independently of that of 
the Dolichoderinae and Formicinae. Yet here again an 
occlusory tract abuts the crop and is the principal feature. 
The filtering slits are irregularly branched; they open into 
a rather simplified muscular portion which is little different 
from the primitive proventriculus of other myrmicines. 
We wish to express our thanks to Dr. A. B. Dawson and 
Dr. W. L. Brown for critically reading the manuscript 
and offering many helpful suggestions. 
References Cited 
Emery, C. 
1888. Ueber den sogenannten Kaumagen einiger Ameisen. Z. Wiss. 
Zool., 46:378-412, pis. 27-29. 
1912. Formicidae, subf. Dolichoderinae. Wytsman’s Genera Insect- 
orum, fasc. 137:1-50. 
1925. Formicidae, subf. Formicinae. Ibid., fasc. 183: 1-302. 
