LOLIGO 161 



buccal membrane of the female is the sperm receptacle. Dur- 

 ing the summer this is usually filled with sperm, and is, ac- 

 cordingly, white and conspicuous. Below the receptacle is a 

 modified area for the attachment of sperm reservoirs as they 

 are delivered from the spermatophores. 



Draw a figure of the female reproductive system. 



Circulatory System. — An injected specimen is desirable. 

 The blood that has been supplied to the body in general is 

 collected by veins and carried to the branchial hearts. The 

 vessels that collect the blood are: 



1. The precavae. A single vessel carries the blood from 

 the head to the anterior ends of the kidneys. Here the ves- 

 sel divides into right and left precavae that are intimately 

 connected with the kidneys. The precavae diverge near the 

 posterior ends of the kidneys and enter the corresponding 

 branchial hearts. 



2. The postcavae. A pair of very large vessels that return 

 blood from the posterior end of the body. They join the cor- 

 responding precavae near the anterior borders of the branchial 

 hearts. 



3. The mantle veins. These return blood to the branchial 

 hearts from the anterior portion of the mantle. 



The blood that is received by each branchial heart is sent 

 into the corresponding gill through a branchial artery that 

 leaves the heart near the opening of the mantle vein, and 

 runs along the side of the gill that is attached to the- mantle. 



The blood is collected from each gill by a large branchial 

 vein that runs along the ventral side of the gill, and enters 

 the systemic heart. 



Draw a figure showing the ^vessels connected with the 

 branchial hearts. 



Expose the systemic heart by carefully removing the 

 superficial tissue between the branchial hearts, and notice that 

 it is not symmetrical. Its lateral angles receive the branchial 

 veins and it gives rise to an artery from each of the other 

 two angles. 

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