CAPRELLIDAE OF WESTERN NORTH ATLANTIC 35 



Caprella acidifrons f. ksludo Mayer, 1903, p. 82. — Chevreux and Fage, 1925, p. 



452, fig. 430t. 

 Caprella acidifrons f. angusta Mayer, 1903, p. 82, pi. 3, fig. 4. 

 Caprella acutifrons f. tibada Mayer, 1903, p. 80. 

 Caprella penanlis. —Stehhmg, 1910b, p. 653.— [?] Hale, 1929, pp. 233-234.— [?] 



Schellenberg, 1931, pp. 266, 272. 

 Caprella penantis f. nalalensis. — Stebbing, 1910a, pp. 465-466. — Barnard, 1916, 



pp. 281-282. 

 Caprella penantis f. porcellio. — Stebbing, 1910a, p. 466. 

 Caprella angusta. — Dougherty and Steinberg, 1953, pp. 44, 47; 1954, p. 171. — 



Johnson and Juskevice, 1965, p. 38. 

 Caprella carolinensis. — Steinberg and Dougherty, 1957, pp. 270-273, figs. 3-7. 



Diagnosis. — Cephalon with anteriorly directed triangular pro- 

 jection; peduncle of antenna 1 not inflated; basis of gnathopod 2 

 shorter than pereonite 2 ; pereopods concave, grasping spines proximal. 



Description. — Body smooth except cephalon with anteriorly di- 

 rected triangular projection. Length of largest male 14 mm, largest 

 female 12 mm, smallest ovigerous female 4 mm. 



Peduncle of antenna 1 not inflated, flagellmn with up to 15 articles. 

 Antenna 2 usually longer than peduncle of antenna 1 . 



Mouthparts typical of genus, lacinia mobihs of right mandible 

 toothed but indistinctly 5-toothed. 



Propodus of gnathopod 1 with 2 proximal grasping spines, grasping 

 margin of dactylus and propodus serrate. Propodus of gnathopod 

 2 with proximal poison tooth, pahn concave in males and slightly 

 convex in females with distal elevated rectangular projection; grasp- 

 ing margin of dactylus serrate. 



Gills usually ovate, occasionally elliptical. 



Propodus of pereopods 5-7 usually with pair of proximal grasping 

 spines, i)ereopods increasing in length from 5 to 7. 



Abdomen of male and female typical of genus. 



Variation. — In the area around Alligator Harbor, Fla., C. 'penantis 

 taken on Leptogorgia showed a reduction or loss of grasping spines 

 on the propodus of pereopods 5-7. Approximately 90 percent of 

 the specimens taken during the summer of 1966 lacked grasping 

 spines and remaining 10 percent had either 1 or 2 grasping spines. 

 Other specimens of this species taken during that summer on algae 

 and hydroids had the usual pair of grasping spines. It is interesting 

 to note that C. cquilibra taken on Lcptogorgia off Virginia showed 

 a reduction or loss of the ventral spine between the insertions of 

 gnathopods 2. 



As I illustrated in 1905 (p. 195, fig. 2a-f) the shape of the propodus 

 of gnathopod 2 changes with an increase in the size of the individual. 

 In smaller individuals of approximately 4 or 5 mm, gnathopod 2 

 resembles gnathopod 1 and bears a pair of grasping spines. As the 



