60 
MR. W. IC. BROOKS ON LUCIFER : 
during tlie daytime, or at least this was the case in every instance which I observed. 
In several cases I found female specimens with a single fresh spermatophore attached 
to the opening (Plate 9, fig. 74, o ) of the seminal receptacle (sr). This opening is 
situated between and a little anterior to the basal joints of the third pair of thoracic 
limbs (P r. 3 of fig. 74). As the spermatophore gradually discharged its contents, it 
was easy to see that both the central core and the investing layer of spermatozoa 
escaped from the outer sheath and passed into the seminal receptacle. In all the 
breeding females which I observed the spermatozoa filled the posterior, and the trans¬ 
parent core of the spermatophore the anterior half of the spermatic receptacle, as shown 
in fig. 74. The ovary is very long (fig. 74, ov), and it lies under the intestine, 
reaching from the fifth abdominal somite to the posterior edge of the carapace, where 
it bends upon itself at right angles and runs down to its external opening, which is 
upon or close to the median line of the ventral surface, a little in front of the third 
pair of pereiopods. The wall of the ovary is so very thin and delicate that I was not 
able to detect it at all except when it was filled with ripe ova. These are very much 
elongated, granular, and slightly opaque ; and there does not seem to be any shell 
around them. They are very elastic, and undergo great changes of shape as they pass 
through the small oviduct. 
Oviposition occurs between 9 and 10 o’clock in the evening, and occupies only a few 
minutes. 
After the eggs are laid they are spherical, transparent, and each one has a rather 
thick shell. They are attached, in a loose bunch of twenty or more, to the last pair of 
thoracic limbs, and in order to save space I have shown them in fig. 7 4, although the 
specimen from which the figure was drawn had not laid any of its eggs. 
As I obtained very few ripe females, I was not able to sacrifice one of them to study 
the reproductive organs under pressure, and I am therefore unable to decide whether 
any parts of this system are double; but I feel confident that there is only one sper¬ 
matic receptacle, and the opening of the oviduct seems to be upon the median line. 
We found a few adult specimens out at sea, but, while I was able to learn little 
about their habits, I think that they are not strictly pelagic, but that their proper 
home is the salt marshes close to the ocean. 
They were met with in the greatest abundance about half-a-mile inside Old Topsail 
Inlet, near a large marsh, during the first hour of the ebb tide, on calm evenings when 
the tide turned between 7 and 8 p.m. ; and I infer that they leave the marshes at this 
time to breed in the ocean. All the mature females which we found, with one excep¬ 
tion, were captured under these peculiar conditions; and we never failed to find them 
at this spot when the tide turned about sunset and the water was calm. 
Owing to this singular limitation there are only a very few favourable evenings for 
procuring the eggs in a single season; and until the animals can be made to thrive 
and multiply in confinement, it must always remain an extremely difficult matter to 
procure the eggs in abundance. 
