Crawford. — Spawning Habits of Spiny Lobster 313 



posed of dense, hard chiton. There are silky tufts of short 

 setae on the dactyl. The pleopods of the female differ from 

 those of the male in the development of the endopodites of 

 the last three pairs, the first pair of endopodites resembling 

 the exopodites. The last three pairs of endopodites are bifur- 

 cated and fringed with long, hair-like setae protruding in tufts 

 from the margins which are reenforced by thickened scutes 

 at these places. All of these hairs are not the same in char- 

 acter, for it is found that some of them are plumose and 

 shorter than the others which are simply rod-shaped. These 

 simple hairs carry the eggs when they are laid. 



The spermatozoa are carried in a vesicle which is deposited 

 on the sterna of the female between the last three pairs of 

 legs. This vesicle has no internal connections with the ovaries 

 and fertilization of the eggs necessarily takes place after they 

 leave the oviducts. The oviducts open on the coxae of the 

 third pair of legs which is anterior to the great bulk of the 

 vesicle. The eggs, therefore, must pass over the vesicle be- 

 fore they reach their place of attachment on the pleopods. 



On May 5, 1919, at the U. S. Bureau of Fisheries Biolog- 

 ical Station at Key West, Fla., a female spiny lobster which 

 had been captured the day before, was observed resting in one 

 corner of the enclosure with the pleon slightly flexed and the 

 margin of the telson resting lightly on the bottom. There was 

 nothing unusual to suggest that spawning was about to occur. 



Presently, the fifth pair of legs was carried slowly fore- 

 ward and the dactyls reached underneath the body in the re- 

 gion of the seminal vesicle. The poking action continued for 

 about five minutes when the spiny lobster was removed from 

 the water. It was observed that the exterior of the seminal 

 vesicle was being scraped off. After replacing the animal in 

 the water, this action continued for half an hour, after which 

 time it was observed that the posterior third of the vesicle 

 was scraped off, showing a pinkish interior. 



Forty-five minutes after the observation started, the move- 

 ments of the fifth pair of legs were quickened and they passed 



