No. 404.] REVIEWS OF RECENT LITERATURE. 667 
actual scientific name. Bdellostoma, like Amphioxus, has its place 
in the history of anatomy, but neither of these terms is the scientific 
name of anything, any more than lancelet is, or hag. Branchiostoma 
is the scientific name of the chief genus of lancelets. 
Homea is the name of this group of hagfishes, Heptatrema and 
Bdellostoma being later synonyms of the same, with no standing in 
scientific nomenclature. For the species of Homea, with an increased 
number of gill openings, Dr. Gill has proposed the name of “ Polis- 
totrema.” There are two species of Polistotrema, P. dombey of 
Chili and P. szouti of California. These are not very much unlike 
and may be really the same thing, though the balance of evidence at 
present favors their distinction as species. If one does not recognize 
the genus Polistotrema, the California hagfish, which is rapidly taking 
its place among the anatomical classics, must be Homea stouti. 
D. S. J. 
Jordan and Snyder on Fishes of Mexico.— In the winter of 
1899-1900 Messrs. Jordan and Snyder made a large collection of 
fishes in the fresh waters of Mexico, especially about Guadalajara, 
Mexico, Aguas Calientes, Puente de Ixtla, San Luis Potosi, and 
Tampico. Forty species were taken, twenty of them being new to 
science, and four new genera, Istlarius (Siluridze), Xystrosus, Falcula 
(Cyprinidæ), and Xenendum (Peeciliide), ; 
The collection indicates that the river fauna of Central Mexico is 
far more abundant and characteristic than had been hitherto sup- 
posed. A most unexpected fact was the large number of very 
closely related species of Pescado del Rey, or Pescados Blancos, 
found in the great lake of Chapala. All are alike excellent as food, 
rich and delicate in flavor. The new species are all figured. These 
are the following : - 
i Sled s, a large catfish from Rio Ixtla, south of the volcanoes 
in Morelos. 
Notropis rasconis, Rio Verde (Rascon), near San Luis Potosi. 
Notropis calientes, Rio Verde de las Aguas Calientes. 
Xystrosus Żopoche, Lake Chapala. 
Falcula chapale, Lake Chapala. 
Characodon encaustus, Lake Chapala. 
Xenendum caliente, Aguas Calientes. 
The genus Xenendum is allied to Goodea, but with bifurcate teeth, 
which, as in Goodea, are loosely attached. The intestines are very 
long, as in Peecilia, but the sexes are similar. 
