(ori) ) 
palmarum. He stated that on making a more minute exami- 
nation he had since found that only the first seven pairs of 
rudimentary abdominal stigmata were visible. No trace of 
the eighth pair could be detected in the normal situation, but 
they were eventually discovered to be fully developed and 
displaced on to the dorsum of their segment, which was 
thickly chitinised, and bore a deep median depression, with 
projecting lateral margins, on the inner faces of which the 
spiracles were situated. Dissection showed that the posterior 
spiracles were the principal agents of respiration, and were 
connected with the larger ends of the longitudinal tracheal 
trunks, the communications of which with the aborted stig- 
mata were very small, and, indeed, could not be detected in 
the somewhat decomposed specimens examined. This dis- 
placement was exceptional in terrestrial coleopterous larve, 
and was similar to that found in aquatic larve. He suggested 
that the rudimentary condition of the lateral abdominal 
spiracles was perhaps correlated with the wet and slimy con- 
dition of the larval burrows, and that the persistence as func- 
tional organs of the prothoracic pair, which was inexplicable 
on this hypothesis, might be due to the fact that the larva is 
stated to return to the outside of the tree along its old burrow, 
which it enlarges, and that the anterior pair might be the 
more important during the later stages of larval life. Neither 
Candéze nor Horn had described the presence of these large 
posterior stigmata in the larva of Rhynchophorus cruentatus 
(=zimmermanni). Dr. Sharp, Mr. McLachlan, and Mr. 
Champion made some remarks on the subject. 
Mr. W. H. B. Fletcher exhibited a long series of bred 
Zygena lonicere and Z. trifolii, hybrids of the first generation 
with the following parentage :—Z. lonicere, male—Z. trifolii, 
female; 7%. trifolit, male—Z. lonicere, female; also hybrids 
of the second generation between Z. trifolii—hybrid, and 7. 
lonicere—hybrid. 
The President enquired whether the hybrids were robust 
and healthy or the reverse. 
Mr. Fletcher stated that many of the hybrids were larger 
than the parent species, and that some hybrids between 7. 
lonicere and Z. filipendule were the largest Zygenid@ he had 
PROC. ENT, SOC, LOND., 1., 1893, Q 
