LARVAE OF DECAPOD CRUSTACEA 405 



Four smaller specimens from the following stations may perhaps be earlier stages 

 of the same species : 



St. 407. 35^ 05' S, 17° 49' E. Two, 16, 20 mm. 

 St. 444. 34° 22' S, 18° 20' E. One, 6 mm. 

 ^f- 1375- 34° 31' S, 26° 19' E. One, 11-4 mm. 



These appear to belong to the genus Palimirtis, but differ from the larva of P. gilchristi 

 in having no distinct palp on the maxillule and in the presence of a group of three spines 

 at the end of the basis of the legs. 



Genus Panulirus, White 



The first Phyllosoma of Pamilinis is described by Nakazawa (1917, P. japonicus). It 

 closely resembles Paliimnis vulgaris but differs in the following respects : 

 (i) Antenna less than half length of antennule. 



(2) Basis of legs, and particularly of leg 3, much shorter. 



(3) Leg 3 very long, but exopod represented only by a very small projection. 

 The dactylus of leg 2 is produced as it is in Palmiirus. 



Crawford and Smidt (1923) give a rough figure of the first larva of Panulirus argiis, 

 which has a general similarity to that of Nakazawa, but apparently in this case the 

 antenna is nearly as long as the antennule, and maxillipede 3 has no exopod. Later 

 larvae have been referred to the genus by Bate (1888), Santucci (1927) and Von Bonde 

 (1932). While there is no direct evidence for the identification of these later Phyllosomas 

 there is no reason to doubt it, and we may assume provisionally the following characters 

 for the genus : 



Characters of the Phyllosoma of Panulirus. 



Fore-body pear-shaped, sometimes very narrow. Hind-body wider, sometimes 

 much wider, than fore-body; generally concave behind. Abdomen small and 

 narrow in early stages. 



Antenna slender. Maxillipedes 2 and 3 with exopod in later stages. Leg 5 

 without exopod. 



The Discovery material contains a large number (about 200) of specimens oi Panulirus 

 Phyllosomas which can be separated into two groups and are treated here as " Form A " 

 and " Form B". While these two groups represent, as I believe, two species only in the 

 Atlantic material, there is much doubt about the specimens from stations east of the Cape. 

 The same general distinction holds good, but there is a lack of correspondence in size and 

 degree of development of appendages in individuals of equivalent stages which makes it 

 fairly certain that other species are represented. Since the legs are almost invariably lost 

 these appendages are not available for specific distinction. Even in the Atlantic material 

 I have found much difliculty in separating the stages in development, since there is much 

 individual variation, and the changes from stage to stage are small. 



