1853] 



PROF. AGASSIZ ON EXTRAORDINARY FISHES FROM CALIFORNIA. 



9T 



intermaxillary does not extend as far back as tlie anterior border 

 of the orbit. The nature of the lips, and extent of the upper max- 

 illary is much as in the other species, but the anterior edge of 

 the socket of the intermaxillaries is above the line of the lower 

 border of the orbit A vertical line through the orbit shows the 

 height of the head in this region to be one-third less than in E. 

 Jacksoni. The opening of the mouth is directed more obliquely 

 upwards. The teeth are more slender,- but have otherwise the 

 same form. In the upper jaw there are twelve,- in the lower eight 

 teeth. The nasal openings are of tolerable size ; one before the 

 other, and in advance of the eye, but slightly below the line of 

 its superior border. The vertical diameter of the orbit is less than 

 its longitudinal; and its posterior border is nearer the angle of 

 the opercle than the snout The preopercle in this species is less 

 rectangular than in the former. The inferior rounded angle of its 

 ridge is iri advance of the posterior margin of the orbit The 

 scales of the preopa-cle are also much smaller and less conspicu- 

 ous. Tubes radiate from the border of the orbit and from the 

 ridge of the preopercle^ as in Emb. Jacksoni. The posterior 

 membranous border of the opercle is narrower : the notch between 

 the subopercle and interopercle is on the vertical line of the pos- 

 terior border of the preopercle. There is a patch of scales above 

 the superior attachment of the preopercle. The dorsal fin differs 

 very little in form from that of the former, but extends somewhat 

 farther forwards, its first spine bsing immediately over the posterior 

 angle of the opercle. The distance from this spine to the end of 

 the snout equals the distance from the same back to the ninth ar- 

 ticulated ray. The posterior rays of the: articulated portion are 

 shorter than in the first species, but they are more numerous by 

 three rays. The pectoral has twenty-one rays ; it is perhaps longer 

 than in the other. The ventrals differ little. The anal fin how- 

 ever, differs greatly: it is very small and contracted, and is placed 

 far behind the ventrals. The scales at its base form a waved out- 

 line much more marked than in E. Jacksoni. The spinous rays 

 are very short, the last being less than one-half the length of the 

 following articulated ray, the base of which latter is directly un- 

 der that of the fifteenth corresponding ray of the dorsal fin. Its 

 posterior base and termination are as in the first species. The 

 caudal fin however, is more slender, and more deeply notched. 

 The scales of the body are by no means so large. The lateral 

 line, follows the outline of the back, as in E. Jacksoni ; there are 

 seventy-five scales in it. 



Color light olive, darker along the back ; light brown longitu- 

 dinal bands extend between the rows of scales, and darker trans- 

 verse bands reach from the back to the sides of the body, not ex- 

 tending below the lateral line in the anterior part of the trunk, 

 but more marked, and reaching nearly to the ; nal fin upon the 

 tail. Head mottled black and white. Dorsal and caudal dotted 

 with black and white. Anal with a large diffuse black mark 

 upon lighter ground. Pectorals white. Ventrals white at the 

 base, terminated with black. 



Only one female has been observed, containing eight young. 

 This species was discovered by T. O. Cary, Esq., in the Bay of 

 San Francisco, in the beginning of August, 1853. 



Directions for Collecting Fl3hes.— By Louis Aga«siz. 



The present condition of our science requires collections made 

 in a very different spirit from those gathered in former years. 

 The naturalist must not only know all the different kinds of ani- 

 mals; he must also .become acquainted with the changes they 

 undergo while growing, and with their geographical range. To 

 arrive at this knowledge, it is necessary to obtain, separately, com- 

 plete collections from every district upon the mainland, from every 

 inlet along the sea-shores, and from every distinct fresh water 

 basin, and to select a number of specimens of every kind, if possi- 



ble so as to include the young as well as the adults, males and 

 females.* The number and diversity of species found in our 

 fresh waters especially, is much greater than is usually sup- 

 posed by accidental observers. A variety of little fishes, some- 

 times belonging even to different families, are almost everywhere 

 used for bait by fishermen, and frequently mistaken under one 

 common name, minnows, are supposed to be simply the young of 

 larger kinds. Among these, most valuable discoveries may be 

 made. There are still districts in our country where a naturalist 

 may fish half a dozen new species and more of these small non- 

 descript^ in a single creek, within a few hours, f A small hand' 

 net is very useful to colltet these smallest kinds of fishes,- and 1 

 have generally found that I could more easily obtain this small 

 fry from boys, than from either fishermen or anglers.- Again, 

 scores of fishes are indiscriminately called ba<s, perch, sivnfishj 

 suckers, etc., in different parts of the country, which, when com- 

 pared side by side, prove as different from one another as a robin 

 and a crow. It is, therefore, a matter of great importance for the 

 naturalist to net every species of fish from every water basin, that 

 he may have an opportunity of ascertaining for himself how far 

 they agree, and how far they differ, in different watercourses.- 

 Anglers and professional fishermen generally know the fishes of 

 their own fishing grounds mitch better than naturalists, and from 

 them most valuable information may be obtained respecting the 

 species inhabiting their neighbourhood. There is, on that account^ 

 no difficult}' in ascertaining from them whether a complete col- 

 lection of all the- fishes of any given locality has been obtained.- 

 But the difficulty begins when it is attempted to identify the fishes 

 of different places, relying upon their names for comparison. Such 

 is the confusion of these names in different sections of the country 

 arising from the use of the same names for different objects, and 

 of different names for the same objects, that nothing short of com- 

 plete collections obtained separately from every important locality 

 will prevent the naturalist from making gross mistakes in his iden- 

 tification of species from remote localities. Few men not trained 

 in the study of natural history are prepared to believe that eveii 

 the fishes living in the' head waters of a river may differ entirely 

 from those living in its middle and lower course, and that it may 

 therefore be necessary to make separate collections in different 

 parts of one and the same water-basin. This is still more im- 

 portant respecting distinct water-systems, But a complete survey 

 ou«ht to cover the wdiole ground as soon' as possible It would 

 not be too much to have one collection for every hundred miles 

 upon our large streams, and one for every fifty and even for every 

 twenty miles upon smaller rivers.- 



The preservation of fishes requires but little care and attention.- 

 Any vessel, jar, can, keg, or barrel fit to hold alcohol, is also fit 

 for collecting fishes, which may be heaped npon it like herrings 

 in salt. The alcohol used must be of about t!:e strength of that 

 that of .88 specific gravity^ for most fishes ; for suckers and 

 brook-trouts, however, it ought to be stronger, about .80, their 

 flesh being either soft or fat, and more readily decomposed. In 

 summer or in warm climates it is advisable to use always strong 

 alcohol to obviate the effects of evaporation. Suppose it is in- 

 tended to make a complete collection from one of the larger tribu> 

 taries of some of our great rivers. A 11 that is wanted will be a 



* There are many species of our fishes in which ihe sexes d.fler as much 

 as among our fowls. 



f" Ii actually happened lo me last winler.at Mobile. Ala.; and at Si. Loui«j 

 Mo., lo discover six and ever eight new species of fishes in a single day. 



J Common whiskey of .90 lo .92 specific gravity may be used by adding 

 strong alcohol, in the proportion ol one gallon of alcohol to one gallon at 

 whisky. Highly rectified whisky as it is prepared in some parts of ihe coun- 

 try, may occasionally d-j by itself, especially il it has nearly ihe specific gra- 

 vity of .SS. It is, however, always safer to err by uiing loo strong lhan loo 

 weak spirits. Specimens may be contracted by loo strong alcohol, and lose 

 lo some extent their form; they will ceriainly spoil entirely in too weak a 

 mixture. 



