486 | PROF. OWEN ON THE ANATOMY 
The part of the ramified ovarian system to which the term oviduct is here applied is 
the tube, o, continued from the common stem of the three last-described tubes, and 
passing backward, inward, and downward, across the cephalo-thoracetral joint, to the 
part of the upper or inner surface of the ‘opercular’ limb, virt, shown in fig. 6, Pl. 
XXXVIII. The termination here of the oviduct (p) was rather prominent: the outlet 
is transverse, and formed by tumid labia, with the inner surface transversely plicate. 
The bifurcation of the hind part of the ovary before passing from the thoracetron to 
the cephaletron, relates mechanically to the accommodation of the cardiac and intestinal 
tubes during the frequent and forcible inflections of the two great body-chambers upon 
each other. The laden ovarium, instead of being pressed down upon the heart (as it 
would have been if it had been continued as a single median and vertically parallel viscus 
across the joint where the cephaletron was depressed at an angle with the thoracetron), 
slips, by its division, on each side the heart during the inflection. A similar relation 
to convenience of package governs the forward extension of the ovarian bipartition in 
relation to the main parts of the heart and intestine. 
The most significant difference between the female organs of Limulus and those of the 
higher or malacostraceous squat-eyed Crustaceans is the absence of the dilated part of 
the oviduct forming the copulatory pouch, or *spermatheca, which absence relates to 
there being no intromission in the act of impregnation in Limulus. 
In the male, the testes are ramified and subreticulate, like the ovaria, and occupy 
almost an equal extent of the two great cavities of the body. The sperm-ducts open upon 
corresponding position of the opercular plate (Pl. XX XVIII. fig. 8, p), their termination 
being on a smaller but rather more prominent cone of thin yellow chitine, at the apex of 
which the sperm-tube terminates by a whitish bilabiate orifice (Pl. XX XVIII. fig. 7, b)*. 
$ 10. Development.—It may not be unacceptable here to give the results of the 
observations of the Rev. Sam. Lockwood, Ph.D., on the generation of the American 
King-crab (Limulus polyphemus), condensed from the account he has consigned in the 
under-cited periodical t. 
In Rariton Bay, New Jersey, U. S., the King-crabs spawn in the month of May, June, 
and July, at the periods of highest tides. In that operation they ascend from the depths 
in pairs, the male holding on to the carapace of the female by his hook-feet (Pls. XXXVII. 
€ XXXVIII. 111). Arrived near the line of breakage of the highest tidal waves, “the 
female digs a hole in the sand, and drops her spawn into it, upon which the male emits 
the fecundating fluid, and the nest is then deserted, the parents returning seawards with 
the retreating tide” $. Occasionally a pair are left exposed by the tide, which they then 
* [Dr. Packard describes the spermatozoa as having a broad oval body, sometimes contracted before the anterior 
end, and posteriorly suddenly terminating in a filament about four times as long as the body (* On the Development 
of the Limulus polyphemus, Ato, Memoirs of the Boston Soc. of Nat. History, vol. ii. p. 156).] 
+ “The American Naturalist, vol. iv. No. 5, for July, 1870. 
t Ib. p. 264. [Notes on the living Limulus are appended to the paper * On the Relationship of the Xiphosura,” 
&c., by Henry Woodward, Esq., F.G.S., communicated to the Geological Society December 20th, 1871; and in 
reference to a remark by the author, that Crustacea, “as a rule, appear to fecundate the ova by a true union before 
the eggs are discharged from the ovaries," the Editor of the * Quarterly Journal' (February 1872) refers to a paper by 
M. Chantran, showing *that the eggs of the common Crayfish are fecundated after expulsion from the oviducts " 
