364 CARL BOVALLIUS, AMPHIPODA HYPERIIDEA. I. 2. PHRONIMlDiE. 



Phronima scdentaria. 



Iii 1861 Pagenstecher gave a detailed morphological description of the animal, 

 and good drawings of the young. He also pointed out the nature of the »house» of Phro- 

 nima, and corrected some erroneous statements given by previous authors. 



In 1862 Spence Bate gave the following specific description of Phronima se- 



dentaria: 



»Antenna? not so long as the cephalon; first joint short, second four times as long. First 

 pair of gnathopoda having the meros inferiorly produced, with the margin serrated; carpus in- 

 fero-anteriorly produced to nearly half the length of the propodos; propodos cylindrical, arcuate, 

 slightly tapering, serrated on the inferior margin with small teeth that gradually increase ante- 

 riorly to every fourth or fifth denticle; dactylos short, terminating in a donhle point, and flanked 

 at the posterior extremity with dactyloptera (this name is suggested for the two wing-like plates 

 on each pair of gnathopoda, and which have not hitherto been described by authors), having 

 the inferior margin of the outer finely pectinated, and of the inner finely serrated: second pair 

 resembling the first, but longer, and having the carpus not so prominently produced. First pair 

 of pereipoda as long again as the gnathopoda, cylindrical, tapering; dactylos minute: second 

 pair like the first, but longer and more robust: third pair having the carpus antero-distally pro- 

 duced to nearly the length of the propodos, cylindrical, robust, tapering, curved, inner margin 

 subcentrally furnished with a projecting tubercle that is tuberculated on the apex and posterior 

 margin, and on the concave margin behind it; propodos long, slender, tapering to a point, ar- 

 cuate, the inner margin being furnished with a tubercle that impinges against that on the carpal 

 process on the distal surface, and tuberculated on the top and on the distal margin as well as 

 the concave surface beyond the tubercle; dactylos obsolete. Two posterior pairs of pereiopoda 

 subequal, having the base long, remaining joints short. Penultimate pair of pleopoda shorter 

 than the other two. Telson rudimentary.)) 



On Phronima custos he said: 



»Third pair of pereiopoda broader than in P. scdentaria, and having the tubercle on 

 the carpal process more tooth-like in form, and that upon the propodos less prominent and 

 smooth. — — — 



The descriptions given by authors of this and the preceding species (= Phronima se- 

 dentaria) appear adapted for either. Without having examined the typical specimens, I can 

 only assume them to be as here named — if, indeed, they are not varieties of the same spe- 

 cies only.» 



Phronima Borneensis, n sp., which must be considered as a synonym to Ph. se- 

 dentaria, he characterized as follows: 



»This species resembles P. custos in the size of the chelate development of the third pair 

 of pereiopoda and in the form of the tubercle on the fixed ramus, and P. scdentaria in the form 

 of the crenulated tubercle on the moveable ramus. 



I can detect no other variation of form in these species from very distant localities: and 

 the union of the specific characters of both the Western species in that from the Eastern Seas 

 suggests the idea, in spite of their distant habitats, that the three forms may be but varieties 

 of one species.» 



In the same year Claus gave the following diagnosis of Phronima sedentaria: 



»Korperform kraftiger und massiger (als in Phronima elongata). Kopf starker aufgetrieben 

 und Thorax gedrungener. Das Abdomen kiirzer, minder gestreckt mit 3 Schwinmifusspaaren 

 und 3 Paaren von Springfiissen. Thoracalfiisse kraftig, die dritten und vierten mit langen, haken- 

 formigen Endgliedern. Die fiinften Scheerenfiisse, ihre untern Glieder angeschwollen.» 



This diagnosis has thus generic value for the distinction from Phronimella, rather 

 than value for the distinction of the species. 



