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PROCEEDINGS OF THE NATIONAL MUSEUM 



there may be more than one postlarval stage during which the animal 

 increases in size but does not develop the characteristic telson morphol- 

 ogy of the adult, although this seems unlikely. In Alima hyalina the 

 last larval stage is almost twice as long as the postlarva; Odontodactylus 

 may have a larger postlarva than juvenile. Under certain conditions 

 Odontodactylus may also have some mechanism of prolonging the 

 larval stage so that postlarvae may be of different size. Finally, 



Figure 8. — Odontodactylus brevirostris (Miers), holotype of Gonodactylus havanensis Bigelow, 

 male, TL 20.0 mm, off Havana: a, front; b, sixth abdominal somite and telson; c, third to 

 fifth abdominal somites in lateral view. 



there may be more than one species involved and two or more species 

 may be represented in the available material. Until more is known 

 about the ontogenetic changes in Odontodactylus, the specimens of 

 that genus, with the widely separate ocular scales, more than five 

 teeth on the claw, and one pair of accessory median carinae on the 

 telson, should be referred to 0. brevirostris. 



