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Thoracic legs I-IV differing from those of adult specimens in nature 

 of segment divisions and minor armature elements (e.g., division 

 between first and second segments of protopodite of second thoracic 

 leg indistinct in female; plumosities on ramal segments not as exten- 

 sive). For nature of legs and armature see figures 21a-/ and table 

 8. Small, platelike projection present just posterior to interpodal 

 plate of first thoracic legs, projection bearing pair of minute nodules 

 from median distal surface. 



Table 8. — Armature of thoracic legs I-IV of the female and viale of 

 Elytrophora brachyptera Gerstdecker, 1853 



♦Numerous, hairlike processes on protopodite not tabulated, 

 f Denticulations very small. 

 JLarger in male than in female. 

 §Not present In immature adults. 



Discussion. — The measurements, descriptions, and figures of 

 the 2 adult stages of Elytrophora brachyptera indicate that a mor- 

 phological change takes place in the transition from the immature to 

 the mature condition. This, however, is not the first time that 

 this has been indicated. Heegaard (1955) points out some of the 

 differences between his immature "Atlantide" material and figures 

 of the adult E. brachyptera. Among these he indicates (p. 46) that 

 the sternal furca in the adult "is delicate with, two long pointed 

 branches with a V-shaped incision between them. In the young 

 'Atlantide' specimens the furca is not fully grown and therefore 

 more plump in the peduncle, shorter in the branches which are 

 more blunt at their points and together shaping a U instead of the 

 V in the adult." This age variation, which is present to a lesser 

 degree in the immature adult specimens used for this description, 



Figure 21. — Elytrophora brachyptera Gerstaecker, 1853, immature adult, right thoracic 

 legs, anterior view: a, first; b, second segment of exopodite of first; c, second; d, third; 

 e, exopodite of third (posterior view); /, fourth. 



