THE AMERICAN LOBSTER. 39 



had also the notion that the male helped the female to place her eggs under the 

 abdomen and glue them to the swinnuerets. 



Apart from the physical impossibility of an internal copulation and fertilization, 

 in the way which many have conjectured, the absence in the Macrura of two important 

 accessory reproductive organs, the vagina and i>it<r>i<tl seminal receptacle, points at 

 once to the fact that the eggs are fertilized outside of the body. With the discovery 

 of an external seminal pouch in the lobster, the function of which had been curiously 

 overlooked or misunderstood until Bumpus called attention to it in 1891 (30), this is 

 still further emphasized. 



As Brocchi and, more recently, Cano (32) have pointed out, the vagina and inter- 

 nal seminal receptacle always occur in the Brachyura in relation to the presence of a 

 male penis (the terminal portion of the efferent duct which is said to be capable of 

 evagination), and imply a different method of copulation. 



The common green crab (Garcinus mcenas), the pairing of which has been repeat 

 edly observed, illustrates this process among the Brachyura. A pair of these crabs 

 was brought into the laboratory at the United States Fish Commission at Woods 

 Hole on the 27th of July. They were adherent solely by the intromitteut organs' 

 of the male, which were introduced into the orifices of the oviducts of the female. 

 The male had a hard shell; the female, which was smaller, a soft shell, conditions 

 which seem to be necessary for copulation, as Oavolini (36) long ago showed, and as 

 Bouchard-Chantraux (21) and Lafresnaye (111) independently observed (25). 



Cano gives the following account of the copulation of Maia (33) : 



The male crab runs to meet the female, lifts her up and places her beneath him, embraces her 

 closely with his feet, and his claws hold her by the margin of the orbits or iu the region of the 

 antennas. In other cases the male turns upon its back, catches hold of the female and draws her 

 upon his belly. The whole action lasts about an hour. 



It is undoubtedly true, as Cano has remarked, that in all the Macrura and Ano- 

 mura, which have no internal receptaculum seminis, penis or vagina, there is no internal 

 copulation and the sperm is never found in the ovary or its ducts. 



THE LAYING OF EGGS. 



In order to determine the time and limits of the breeding season of the lobster, it 

 is necessary to collect and examine a large number of their eggs at different places 

 and at different times of the year. The examination of the winter or summer eggs 

 alone will not suffice to solve the problem, as I have learned by my own experience, and 

 this explains why the question has been the subject of so many conflicting statements 

 and has remained uusettled down to the present day. (For a review of this question 

 see jSos. 98 and 101 of Bibliography.) 



The following quotations illustrate the confusion which has surrounded this 

 important subject. Verrill (196) remarks: 



There is a great difference iu the breeding season on different parts of the coast. The lobsters 

 from New London and Stonington often lay their eggs as early as the last of April or first of May ; 

 while at Halifax Mr. Smith found females with recently .laid eggs in September. At Eastport, Maine, 

 the females carry their eggs in midsummer. 



1 The only intromittent organs noticed in this cnse were the slender wand-like appendages of the 

 first abdominal somite. The penis is probahly introduced after the former have been withdrawn. 

 (Compare p. 37.) 



