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PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 42. 



twenty lamellae altogether. The uropoda are rudimentary, m the form 

 of two oval sac-like bodies. There are five pairs of incubatory plates, 

 which do not entirely inclose the marsupial pouch on the ventral side, 

 but come very close together, leaving only a small opening; the first 

 pair has the terminal lobe of the distal segment long and narrow and 



produced straight back- 

 ward. (See fig. 4.) 



All the legs are prehen- 

 sile and are furnished with 

 a carina on the basis. 

 (See fig. 3.) 



The male is long and nar- 

 row, nearly'- three times as 

 long as wide. The head is 

 large, with the anterior 

 margin widely rounded ; 

 the posterior margin is also 

 rounded and deeply set in 

 the first segment of the 

 thorax. (See fig. 2.) The 

 eyes are vanishing. All 

 the segments of the thorax 

 are distinctly separated. 

 The first four segments of 

 the abdomen are also more 

 or less distinct. The fifth 

 and sixth are fused to form 

 a large terminal piece, the 

 lateral incisions alone in- 

 dicating the two segments. 

 The uropoda are absent. 

 There seem to be no pleo- 

 poda. 



This species is parasitic 

 on MacrobracTiium young (either jamaicense or olfersii) being found in 

 the branchial cavity. It was collected by Doctor Meek and Mr. 

 Hildebrand in a small creek, Atlantic slope, Culebra, Canal Zone; in 

 the upper Trinidad River, Panama; in the Rio Masimbar, Empire, 

 Canal Zone; in the Rio Frijoles, Frijoles, Canal Zone; in the Agua 

 Clara Creek, Panama; in the Gatun River, above Mitchelville; and 

 in the upper Trinidad River, Panama, on Macrohrachium jamaicense 

 (Herbst). 



The type from -the first-named locality is in the United States 

 National Museum, Cat. No. 43502. 



Figs. 1-4.— PALffiGYGE meeki. 1, Female, X 5|; 2, Male, x 

 23; 3, Sixth leg of female, X 54§; 4, First incubatory 



PLATE OF FEMALE, X 19J. 



