412 MR. G. A. BOULENGER ON LUCIOPERCA MARINA. [May 17, 



hitherto little-understood L. marina, it will be found that the 

 Europaeo-Asiatic and American species form two well-marked 

 groups ; the former {L. sandra and L. volgensis), characterized by the 

 lesser space between the ventrals and the greater development of 

 the ventral and anal spines, is nearer related to Perca, with which 

 it is connected by L. volgensis, a fish almost as much a true Perch 

 as a Pike-Perch ; the latter (Z,. canadensis and L. vitrea) charac- 

 terized by the wider separation of the ventrals and weaker ventral 

 and anal spines. 



These two groups are so well marked that one might feel tempted 

 to treat them as distinct genera, were it not for the information now 

 afforded by L. marina, which although agreeing in most respects 

 with the American L. canadensis, yet differs from it in the more 

 approximate ventrals, in this point resembling its European con- 

 geners, and thus forming a very interesting connecting group, as 

 may be seen from the following synopsis of the five species which 

 constitute the genus Lucioperca^. 



I. The distance between the ventrals about two- 



thirds the width of their base ; ventral and 

 anal spines free. 

 Canine teeth weak, or altogether absent in old 

 specimens ; D. XH-XIV, I-II 21-22; 



A. II 9-10; Sq. 110-117 ^^gj; L. 1. 71- 



83^ 1. volffciisis, Pall. 



Canine teeth very strong ; D. XIII-XV, I-II 



19-23: A. II 11-12; Sq. 132-150^111; 



L 1.80-95 -2. sandra. h. 



II. The distance between the ventrals about two- 



thirds the width of their base ; ventral and 

 anal spines very feeble and closely attached 

 to the soft i-ays. 

 D.XII-XIIL t-II (12?) 16-17; A. II 11- 



12; Sq. 115 ~° ; L. 1. 78-84 3. marina, 0. A V. 



III. The distance between the ventrals equals 

 the width of their base ; veutral and anal 

 spines very feeble and closely attached to 

 the soft rays. 



Top of head and cheeks closely scaled ; back 

 flattened; D. XII-XV, I-II 17-19; A. 



II 11-12; Sq. 110-125 2^; L. 1. 80- 



90 4. canadensia, C. H. Smith, 



Top of liead and cheeks entirely or partly 

 naked; D. XII-XIV, I-II 19-21; A. 



II 12-14; Sq. 110-132^; L. 1. 86- 



95 5. vitrea, Mitch. 



' Lucioperca should date from the first edition of the 'Eegne Animal,' 1817, 

 where Cuvier (p. 295) does use the Latin name ("ce qui leur a fait donner le 

 nom de liKioperca"), although indirectly and without a cajjital. 



^ The transverse series of scales are counted along the back, a little above 

 the lateral line; the longitudinal series are counted at the highest point 

 between the spinous dorsal and the lateral Une and between the latter and the 

 mid-ventral Une ; under L. I. the number of perforated scales is given. 



