THE ISOPOD CRUSTACEA 



159 



Head widening posteriorly, its antero-hitcral angles being produced 

 into lobes, directed upward. Eyes absent. The thoracic segments 

 have their lateral margins somewhat elevated and contiguous. The 

 abdominal segments are not contiguous along the lateral margins but 

 are separated by broad lateral incisions. 



The incubatory lamelloi are very wide apart, surrounding a broad 

 open space, the marsupium, on the ventral side of the body. 



Fig. 3, Bopyrus alphei, 9 ■ 



Fig. 4. Bopyrus alphei, $ . 



Pleopoda simple, lamellar, placed on either side of the median line. 



Color, white. 



Male, oblong oval. Eyes wanting. Thoracic segments well de- 

 fined. Abdominal segments imperfectly defined, except along the 

 margin. Color white. 



Type locality. — Mangroves, Rio Parahyba do Norte, Brazil, in the 

 branchial cavity of Alpheus heterochcBlis Say. Cat. No. 23759. 



