130 MR. W. E. HOYLE ON THE [Mar. 5, 
Towards the margins of the pads the peculiarities of the epithelium 
gradually disappear. The cells become shorter, their nuclei more 
deeply stained, and they pass by insensible degrees into the flattened 
pavement epithelium which lines the rest of the siphon. At the 
anterior extremity of the organ it is raised up into a free process, 
which is completely surrounded by the layer of these highly refractive 
bodies. 
I have also examined sections of this organ in the case of Taonius 
both young and adult, in the embryos of Ommastrephes, Sepia, and 
Loligo. In its general features the minute structure of the organ 
is the same in all these instances, but it was only in Gonatus that I was 
able to discover the highly refracting globules described above. What 
the relation of these may be to the fusiform rods described by 
Miller and Boll I will not attempt to decide at present, but must 
leave any further histological discussion till an opportunity offers 
for describing its structure in Taonius and other forms where it is 
highly evolved. 
I shall, however, venture a suggestion as to the function which it 
possibly discharges, because a hypothesis, even though it may 
eventually prove to be mistaken, affords a useful guide in subsequent 
researches. The theories of a sensory or of a phosphorescent pur- 
pose in this organ seem to be sufficiently negatived by its situation 
in a closed space through which only effete products from the body 
are discharged. Brock is, 1 think, in error when he states that the 
main interest of this organ is that it affords an instance of the occur- 
rence in Mollusca of nettle-cells or of bodies allied to them. Tom 
mind the resemblance to nettle-cells is purely superficial. Miller, 
who noted it, distinctly remarks that they have no filament, and 
Boll, as above mentioned, did not think that they were so much like 
nettle-cells as like the rod-bearing cells of the Turbellaria—an opinion 
which is fully borne out by his figures. The view that the modified 
epithelium discharges some secretion seems on the whole the most 
feasible, and is supported by the existence of the structureless layer 
observed on the surface of the epithelium, which, it may be remarked, 
is of considerable thickness in the adult Taonius. The difficulty 
hitherto has been to discover the purpose served by this secreted 
matter. 
I would suggest that possibly this funnel-organ is an apparatus 
for the closure of the funnel, that it is, in fact, functionally, though 
not morphologically, a valve. 
I am led to this conclusion by the following considerations :— 
1. The fact that in a very large number of sections which I have 
examined the pads are so disposed as to very nearly, if not quite, 
occlude the lumen. I need only refer to the two instances figured 
in the woodcut as examples. 
2. The fact that in those forms in which the organ is most highly 
differentiated in the adult the valve is absent, as for example in the 
genus Taonius. 
3. In this case the presence of a sticky or viscous secretion would 
be of obvious utility in securing the more perfect apposition of the 
