REPORT ON THE AMPHIPODA. 155 



young. It should be remembered that througliout this portion of the work the Crustacea 

 in general are dealt with, and that therefore, when the Edriophthalma are not being described 

 in especial, many of the observations made are calculated to throw light upon their 

 structure. 



In the chapter on classification, after noticing earlier systems, Milne-Edwards explains his own. 

 He prefers the zoological method which is not daunted by great differences of structure 

 from grouping animals of high organization with others in which it may be far less complex, 

 yet of the same general type and recalling " les 6tats transitoires par lesquels les etres les 

 plus parfaits de la serie out pass6 pendant la duree de leur vie embryonnaire." He gives 

 the definition of the class as follows : — 



" Crustac^s. Animaux ayant le corps divise en anneaux, en general tres-distincts, mobiles et d'une 

 consistance assez grande (comes ou calcaires), sans squelette interieur proprement dit, etportant 

 une double serie de membres, presque toujours bien distinctement articules, et constituant des 

 antennes, des mdcJwires, etc., et des pates dont le iionihre est, le plus ordinal rement, de cinq 

 ou de sept paires ; le systkme nervetix, en general bien distinct, ganglionnaire et longitudinal ; 

 la respiration en general aquatique, et se faisant toujours d I'aide de branchies ou de la peau ; 

 la circulation, en general bien distincte; presque toujours un crmir aortique et des vaisseaux 

 sanguins pr'opres ; les sexes separes." p. 231. 



He makes three subclasses, namely the Crustac6s maxill^s, Crustac6s suceurs, and Crustac^s 

 xyphosuriens. The first of these he subdivides into various legions, the first of which, les 

 Podophthalmiens, contains two orders, the Decapods and Stomapods, while the second, les 

 Edriophthalmes, contains three orders, the Amphipods, Isopods, and Laemipods. 



It is in treating of the Decapods, p. 243, that he mentions the designations which he says are 

 often applied to the six joints into which the ambulatory foot is commonly divided. These 

 terms are 1. hanche, 2. trochanter, 3. cuisse or bras, 4:. jambe ov carpe, 5. metatarse, 6. 

 tarse or doigis. The last two of these sometimes, "disposes en mani^re de pince," form a 

 hand (main). 



The Atlas, plate xi. fig. 1, repeats the diagram of the nervous system of Talitrus given in the 

 earlier work. 



1834. EOUSSEL DE VaUZ^IME, AUGUSTUS. 



Memoiee S'U7' le Cyamus ceti (Latr.) de la classe des Crustaces. Annales 

 des Sciences Naturelles. Kddigees pour la Zoologie par MM. Audouin et Milne- 

 Edwards. Seconde Serie. Tome premier. — Zoologie. Paris, 1834. pj). 239-255. 

 257-265. Pis. 8. 9. Fig. 19. 



The author explains that he was able to study the.se parasites from a great number of whales 

 harpooned under his own eyes in the Atlantic, in the neighbourhood of Tristan da Cunha, 

 and off the Falkland Islands. He distinguishes three species, which he thinks had been 

 hitherto confounded by authors under the same name. Liitken points out that all the three 

 species are distinct from the northern Cyamus mysticeti, with which Eoussel de Vauzeme 

 supposes his Cyamus ovalis to be identical. Of this species the anatomy is very fully 

 described. The mistakes of Savigny and Treviranus are pointed out. Among other details 

 of his own investigations, he says, "Des perquisitions inutiles pour trouver les glandcs 

 salivaires, m'ont fait remarquer souvent dans les tuniques deTestomae des matiferes blanches, 

 friables, de forme vari^e, dont je n'ai pu determiner la nature, k moins qu'elles ne soient 

 analogues aux pifeces calcaires qu'on presume servir a la reparation du test chez les crustac6s." 

 He remarks that there is " parmi les viscferes une membrane diaphane, parsem^e de points 



