220 Dr. W. E. Collinge on the 
it is exceedingly difficult to state what the true function 
of these glands is; their presence, however, in so many 
genera and species is at least indicative of their importance. 
Max Weber (9) regarded them as in some way conuected 
with the organs of respiration, but there is little or no 
evidence to support such a view. 
Huet (3), whilst confessing that it was easier to state in 
what way they do not serve than to assign a function to 
them, suggests that possibly they are connected with the 
disagreeable odour which the Terrestrial Isopoda possess, and 
that added to this the secretion may havea disagreeable taste 
to enemies. 
In Porcellionides pruinosus the secretion is, at times, very 
copious. A few living specimens were dropped into 90 per 
cent. alcohol and after a few minutes removed, when it was 
found that they were more or less bound together im a 
bundle by reason of the viscous strands of the secretion. 
The same result was obtained when specimens of Porcellio 
dilatatus were treated in a similar manner. 
The former species exhibits in life a very beautiful 
“bloom ” over the whole of the dorsal surface of the body, 
but whether it is in any way due to the secretion of the 
cutaneous glands we have no direct evidence. Jour 
specimens of this species were taken and the “ bloom ” very 
carefully removed by wiping it off with a piece of soft silk, 
but on examining these specimens twenty-four hours later 
it was just as plentiful as on those specimens from which 
it had not been removed. 
Careful experiments show that the secretion is more 
copiously extruded after the animal is disturbed. Speci- 
mens of P. dilatatus were confined to a small petri dish and 
frequent attempts made to pick them up with a pair of 
forceps. After chasing the specimens about for two or three 
minutes, one could, by holding a specimen in a pair of forceps, 
easily see large quantities of the secretion along the pleural 
plates of the mesosome and more particularly so on the 
metasome andthe uropoda. There is no difficulty in drawing 
off strands of 15 to 80 mm. in length. 
Attempts were made to collect some of the secretion, 
though unsuccessfully, but when it was drawn off by the 
fingers its peculiar and disagreeable odour was easily 
recognized, it being faintly discernible even after washing the 
hands. 
From the above imperfect data I am inclined to agree 
with Huet that the function of these glands is to secrete a 
Te) Yn 
