34 
of diptera. The two terminal flaps of the 
proboscis represent the labial palpi. The 
trachea-like internal structures are not real 
tracheae, but simply supports of the flaps. 
Parallel to the large trunk of these false 
tracheae, is the labial nerve, which soon 
divides into two parts, and sends a multi- 
tude of ramifications to the periphery and 
inner surface of the flaps. The former 
terminate in the marginal, well developed, 
hairs; the latter in the rudimentary hairs 
of the inner surface, which are reduced to 
a minute chitinous cylinder. The nerve 
filament that goes to a hair ends in the base 
of the latter ; but in the rudimentary hairs 
the filament traversing the cylinder projects 
beyond. These are probably gustatory, 
and the former tactile. 
Mr. V. T. Chambers® describes the 
structure of the tongue in some hymenop- 
tera. In the Apidae he decides it is a 
sucking organ, but not in the Andrenidae. 
The honey in the former passes through a 
hollow colorless tube open at the apex, 
with a smallest diameter of 1-20th of a mil- 
limetre ; but in the latter this tube is imper- 
forate at the apex. Mr. J. D. Hyatt also 
discusses * the same subject, differing, how- 
ever, from Mr. Chambers, in believing the 
colorless rod to be open along the median 
ventral line, and applied to the ventral, 
instead of dorsal, internal aspect of the 
tongue itself. Both writers are unfortu- 
nately unacquainted with the recent descrip- 
tions of Wollf and Graber. 
Mr. Chatin compares™ the labium in 
the orthoptera with the maxilla, and finds 
that the pieces of the latter have homolo- 
85 Journ. Cincinnati Soc. Nat. Hist., v. 1, p. 40, 
161. 
35 Amer. Quart. Micr. Journ., v. 1, p. 287. 
87 Comptes rend., vy. 87. 
PSYCHE. 
Locusta viridissima 
is taken as an example. 
I have myself attempted ® to describe 
the structure of the head, and more par- 
ticularly of the maxillae, in the Psovidae. 
The latter are remarkable for their fork- 
like appendage, the morphology of which 
is not clear. Supposed salivary recepta- 
cles are also described. 
The most valuable paper relating to the 
digestive system is Dr. E. Schindler’s 
monograph® on the Malpighian vessels. 
After the usual prefatory history of the 
conflicting views as to their function, Dr. 
Schindler describes these organs in detail 
in the orthoptera. Histologically, by the 
way, each tube shows (1) a serous mem- 
brane, (2) a delicate tunica propria, (3) 
the glandular epithelium, and sometimes 
(4) an intima with pores. The author 
could not find the vessels in Thysanoura ; 
in Lepisma, however, he believes there 
are eight arising from the posterior end of 
the chylific stomach. In Mantis they are 
inserted at the end of the first third of the 
small intestine. The Malpighian tubes in 
the Gryllidae, as well known, are remark- 
able in the possession of a common excre- 
tory duct, which Dr. Schindler finds has 
The term- 
inal appendages, imperfectly.described by 
Sirodot, are shown to belong to the con- 
nective tissues, and have not in any way 
an excretory function. Heidenhain’s sul- 
phindigotate experiment was tried with 
Gryllotalpa and Locusta (by injections of 
course), and the Malpighian vessels were 
found to act just like the mammalian urin- 
38 Proc. Bost. Soc. Nat. Hist., v. 19, p. 291; also 
Psyche, v. 2, No. 45. 
39 Zeitschr. wiss. Zoologie, v. 30, p. 587. 
gues in the former. 
a peculiar muscular envelope. 
