M. T. Thorell on two European Argulidse. 161 



rarius albo punctatum, vittis in utraque ala 3 violaceis, parallelis, 

 versus apicem scnti latioribus et confluentibus, et linea tenui, obscurius 

 violacea, antice introrsum geniculata, inter vittas duas interiores ducta. 

 Lobus frontalis margine subviolaceo. Rami gastrici luteo-fusci. 

 Ovarium in dorso perlucens album, dense violaceo punctatum, linea 

 media ad longitudinem ducta, purius alba geminatum. Cauda scuto 

 pallidior, densius albo punctata, versus apicem et in margine externo 

 pallide violacea, vitta violacea ad marginem internum, receptaculis 

 seminis obscure fuscis. Truncus subtus in medio late fuscus, in 

 lateribus albicans, ipso margine cum stipite pedum cseruleo-virescena. 

 Denies corporis, partium oris, maxillipedum cet,, cum annulo 

 cliitinoso cotyledonum fusci. Partes oris ceterum, ut rami pedum, 

 hyalinae. 



With regard to the internal conformation of the animal, I have 

 only the following to communicate. It differs from A. foliacetcs 

 in the fact that the large side branches of the stomach send out 

 smaller branches, not only on the outer but on the inner side 

 also. The outbranchings of the stomach are on the following 

 plan : — Immediately before the first pair of legs the stomach 

 sends out on either side a strong, outwardly and somewhat 

 backwardly directed stem, which, when it has attained almost 

 the middle of the wing of the shield, bends backwards at almost 

 a right angle, sending immediately a strong stem forwards. 

 This divides soon after into two smaller stems, which stretch 

 backwards towards the end of the shield, and on either side 

 send forth numerous branches and subbranches, which, however, 

 never anastomose with one another. Even the short anteriorly 

 directed stem branches forward in the same manner. In all 

 these vessels the rhythmical pulsating backwards and forwards 

 of the brownish-yellow contents is perceptible in the living 

 animal. The circulation of the blood is particularly evident in 

 the broad and thin tail. 



The ovarj/ reaches far forward between the second pair of 

 footjaws, and is therefore somewhat pointed at its anterior 

 extremity. It is long and narrow (7 millim. long, 2 milhm. 

 broad), and contains a great many eggs, closely packed and 

 adhering together, about ^ millim. in length and | millim. in 

 breadth. The eggs show the same formation and appearance 

 as in A. foliaceus and A. coregoni. In the living animal the 

 ovary is transparent through the back as a whitish, thickly 

 violet-dotted organ, divided lengthwise by a clear white band. 

 Of this fine species I obtained a single specimen in Nice on the 

 8th March, 1862, a female, fastened upon the inside of the pec- 

 toral of Pagellus erythrinus, Cuv. The right lobe of both the 

 head-shield and the tail are somewhat shorter in this specimen 

 than the left, which is undoubtedly only an accidental variation. 



Risso found this species at Nice, in the month of May, on 

 Ann. ^ Mag. N. Hist. Ser. 3. Fo/. xviii. 12 



