Show I r NOTES ON THE BRINE SPINE SHRIMP I f THERE is a very popular error to the thet t e effect that the Great Salt Lake is entirely devoid of life either animal or vegetable Indeed writers of our schoolroom schoolroom schoolroom school school- room geographies have until very recently made such statements Every well informed person of today however knows that not only do we find life in inthe inthe inthe the briny waters but several forms of oi life both animal and vegetable It is true these plants and animals b belong long to the lower forms and that some are almost microscopic in size The plants The Artemia Verrill Verrill or Brine Shrimp This belongs to the division division division divi divi- sion of the class to the order oda and to the sub-order sub Bran- Bran oda Or according to Packard to the order oda and the sub-order sub This is one of the largest and most conspicuous forms of lake life The characteristics of the genera to which it belongs have been given as follows Eight abdominal segments without appendages the second antennal clasp- clasp A. A B. B i s 1 1 R ip y i f l I 4 r t gitl Jt 1 6 Y r J jl ii j fJ t I i f t t r. r 1 t f mil u tH BRIN BRINE SHRIMP Artemia Arlem fer s. s A MALE MAL B F FEMALE l From photomicrographs taken by Dr J. J E. E Talmage f have not as yet been fully identified but the animal forms so far discovered are four in number and are classified as follows 1 The larvae of one of the belonging to the Di Dieters and identified as probably cus eus Packard 2 the larvae of a species of the Corixa identified as probably probably pro pro- bab bably y Corixa Uhler 3 the larvae and also the pupa of a fly identified identified identified fied by Packard as E hydra I f The pupa cases of this fly are washed ashore in great quantities at certain seasons and as they decay there they give rise to a most obnoxious odor 4 ers en of the male have their second joint flat and triangular while the is short The tiny creature is about one fourth of an inch long is practically made up of tissue possesses no covering and reminds one at a hasty glance of the ordinary wiggler though more careful careful careful care care- ful examination shows a wide difference in structure As will be seen from Cut CutA A the head of the male differs very much from the head of the female The large claspers on the male male are are plainly visible on the living specimen to the unaided eye The eyes are stalked and stand i. i x f out from the head a a considerable distance distance distance dis dis- tance looking under the microscope not unlike great black hemispheres The body proper consists of a long 1 straight tube or channel through which the digestive tract may be clearly traced f as a black more or less coiled thread This feature may be distinctly seen in both cuts The legs 22 in number are attached to tog g the sides of the body 11 on n a side These have large paddle-like paddle exp expansions by y means of which they swim Through 1 these expansions circulates the fluid corresponding to blood and in them is r accomplished the aeration of this fluid Indeed it is from this fact that the suborder suborder sub sub- order receives the name oda which means literally lung footed The creature may be found in the lake at all seasons of the year though in greatest abundance during the summer summer summer sum sum- mer months In the winter they are areF F found in the deeper portions of the lake t and at a considerable distance below the surface During the summer months they occur in great num numbers bers near the theY Y f lake shores and very near the surface According to Dr Talmage the creature shows a wonderful power of adaptation to tor r variations both of temperature and of the density of ot the water He reports i having taken them from the lake in the midst of winter when the temperature of oi the water was far below the freezing point They were found in the salt ponds when the water was very near the point of saturation and they lived there apparently at ease He conducted experiments which went to show that dilution of the lake water affected them but slightly He kept living specimens for days in m lake water diluted with twenty-five twenty fifty eighty and even ninety per cent fresh water without their showing showing showing show show- ing signs of inconvenience Indeed several specimens retained life for some sometime sometime sometime time in fresh water only In all cases however the changes were made graf gra gra- gra f o dually These experiments in changing the media were not carried on sufficiently long to result in any considerable change of structure in the animal It is presumed pre pre- however that marked modifications modifications modifications would follow were the changes kept up for several generations Such has been found to be t the e case in Europe Professor J. J S. S Kingsley after pointing pointing pointing point point- ing out the characteristics of the genus to which the Artemia Anemia belongs and contrasting contrasting contrasting contrast contrast- ing them with the characteristics of the 1 says U Under or ordinary inary circumstances these would be considered as of generic value but what shall we say when we know the results of the observations and experiments experiments experiments ex ex- j of the Russian naturalist Vladimir Condensed from this account these were as follows In 1871 the spring flood broke down down- the barriers separating the two different lakes of the salt works near Odessa diluting the water in the lower portion to 8 80 Beaume and also introducing into it a large num number ber of the brine shrimp Artemia salina After the re restoration restoration restoration re- re of the em embankment the water rapidly increased in density until in September 1874 it reached 25 of 3 Beaume's scale and began to deposit deposit deposit de de- posit salt With this increase in density density density den den- sity a gradual change was noticed in inthe inthe inthe the characters of the Artemia until late in the summer of 1874 forms were produced which had all the characters of a supposed distinct species A. A mt ehl hat The reverse experiment was then tried A small quantity of the water was gradually diluted and though conducted for only a few weeks a change in the direction of A. A salina was very apparent Led by these experiments experiments experiments ments he tried still others Taking Anemia Artemia salina wh which ch lives in brine of moderate strength he gradually diluted the water and obtained as a result a form which is known as SCh the te last segment of the abdo abdo- JI r- r Imen men having become divided into two N Nor or is this change produced by artificial means alone The salt pools near Odessa after a number of years were converted converted converted con con- into water fresh-water pools and with the gradual change in character Artemia sauna sahna produces first a species known as s and at a still lower densi density ty lecta f rox and another species described as B. B In Interesting Interesting Interesting In- In results will dou doubtless follow similar experiments with our own shrimp p. p One of the most interesting features connected with the Shrimp is its method of reproduction This is or reproduction by means mean of unfertilized eggs Briefly stated this method is as follows In the spring of the year the females lay eg eggs s which when hatched produce only females and from the hatching of this brood until the fall few if any males can be found These young females in turn also lay eggs unfertilized which hatch only females and this goes on during the entire summer In the fall a brood is hatched containing males and females and reproduction reproduction reproduction re re- production then is normal The food of the shrimps is said to be bethe bethe bethe the algae which is found in such great abundance in the water of the lake The shrimps when properly cooked are pronounced very palatable and it may be that one of the many industries of Utah as yet undeveloped is the catching and canning of shrimps found in the Great Salt aLke Ir |