Cutaneous Glands in the Terrestrial Isopoda. 215 
regarded as unicellular bodies, in the metasome, he found 
them in the 5th, 6th, and 7th segments of the mesosome in 
the Trichoniscide, Ligidium, Philoscia, and Porcellio pictus. 
He speaks of the excretory canals as one joining the other 
before opening externally, whilst others terminate by an 
aborization of slits or ‘‘ Spatten.”’ 
Still later, Huet (2 & 3) studied the structure of these 
bodies. His account differs in many details from both that 
of Lereboullet and Max Weber. ‘The full details were set 
forth in 1883. 
According to this author the glands are not compound, 
but agglomerated unicellular glands ; they are lobed, and each 
contains two nuclei. Between the two nuclei he describes a 
hollow cavity or vestibule, from which the excretory canal 
proceeds. The canals never join one another, each opening 
by a separate pore. 
Like Max Weber, Huet observed the glands in the meso- 
some as well asin the metasome*. In Porcellio levis, he 
states that they are present in all the segments of the 
mesosome and metasome, the former haying peculiar sieve- 
like openings “‘on the superior face of the epimeres, quite 
close to their edge.... The number of openings in each 
sieve indicates the number of glands occupying each epimere. 
It is about 30 to 35 in Porcellio levis.” The glands of the 
metasome open in a groove on the external side of the 
external articulation of the uropods, the openings being 
arranged in linear series. 
In P. scaber they are described as being similar, but in 
addition the glands of the last three metasomatic segments 
have proper openings, but these are not present on segments 
1 and 2, which are partly covered by the posterior portion 
of the mesosome. ‘They are present in the telson, he states, 
and open as usual on the uropods. 
In P. frontalis (= Porcellionides pruinosus, Brandt) he 
states that they only occur in the metasome and telson, and 
all open on the uropods. ‘The same condition obtains in 
Oniscus and Armadillidium, according to Huet. 
In Ligia oceanica, the Marine Isopoda, and in Asellus 
aquaticus they are stated to be absent, and not present in the 
embryo or newly hatched isopod. 
* On p. 365, Huet draws attention to the fact that Max Weber had 
pointed them out “not only in the metasome, but also in the 5th, 6th, and 
7th segments of the thorax or mesosome in the Trichoniscide, then in 
Ligidium, Philoscia, and Porcellio pictus,” but on p. 370 (op. cit.) he says 
“Max Weber, who has only seen them on the posterior segments of the 
body,” ete. 
