284 



ZOOLOGY 



this position of the branchiae ; in each segment it gives off a 

 pair of lateral arteries, and in front it ends in ophthalmic and 

 antennary arteries (Fig. 165). 



The liver extends into the abdomen, and is divided into 

 ten pairs of caeca. A pair of glandular diverticula open into 

 the rectum near the anus ; they are regarded as excretory. 



Fig. 165. — A SquiUa mantis, with the 

 shell removed from a portion of 'the 

 dorsal surface to show the internal or- 

 ganisation. After Leuckart and Nitsche. 



1. 1st pair of antennae. 



2. 2nd pair of antennae. 



2^. Scale, exopodite, of 2nd antenna. 



3. 2nd maxillipede. 



i. Heart, with thirteen pairs of ostia, and 

 numerous paired vessels supplying 

 the limhs. 



5. Median unpaired vessel supplying the 



eyes and antennae. 



6. Ovary. 



7. Oviduct opening at base of (8) in Fig. 



164. 



8. Stomach. 



9. Liver diverticula from the intestine, 



these lie under the ovary. 



10. 6th abdominal appendage. 



The generative organs also lie in the abdomen, the oviducts, 

 however, reaching into the three free thoracic segments, being 

 situated between the alimentary canal and the heart. The 

 vas deferens opens on the last pair of thoracic appendages, the 

 oviduct on the last but two. An antennary gland does not 

 appear to be present. 



Unlike most Crustacea, the Stomatopoda do not carry their 

 eggs about with them, but deposit them in the burrows in 



