ee General Notes. [ May 
‘Von Lendenfeld Mats that the reason why these organs have 
escaped observation by all who. have studied living Sponges is 
that they are ordinarily retracted, and he recalls certain obser- 
vations which he had peee made on the retracted sense- 
organs of other sponges. He hints at interesting comparisons 
of these with some of the peculiar sense-organs “of the higher 
Metazoa, but without entering into any detail. 
Organ of Smell in Crepidula.—The organ of smell, or os- 
phradium, of gasteropod molluscs is a patch of sensory epithe- 
lium, which is placed in close relationship with the two normal 
gills with which these animals are provided. In many forms, 
however, one of these gills is aborted, and occasionally its place 
is taken by another branchial organ (e, £., Patella), which has no 
rinse to the typical branchiz. In many forms there is also 
what is known as the rudimentary gill; but Spengel has shown 
that this i is not respiratory in its function, but is rather a sensory 
organ, variously modified in its appearance. Dr. H. L. Osborn 
describes (Zool. Anzeiger, x. I 18) this osphradium as it occurs in 
Crepidula fornicata. In this species the gill fills almost the entire 
mantle-cavity, but on the left of the gill-ridge is a low ridge of 
eighteen or twenty papillz, each with a globular head and a 
short peduncle. This is the osphradium. The ridge from which 
each papilla. In addition to this Dr. Osborn notices the exist- 
ence of a peculiar high epithelium clothing the osphradial ridge, 
_ which differs from that on any other part of the mantle, and 
forms what appears to be a specialized organ. In this connection 
it may be mentioned that an investigation of the relations of 
osphradium to branchiz in the limpet Acmza would be produc- 
tive of important results in settling the affinities of the family. 
A Larval Galeodes.—The Arachnida of the sub-order Soli- 
fugz are so little known that Croneberg’s recent description of 
a larval stage of one (Zool. Anzeiger, No..247, 1887) is worthy of 
nti 
had been forced into the ra ene on as the 
foresee $ is now more ovoid, while the latter, as well as append- 
ages, are greatly distended. The cephalo-thorax at abdomen 
