368 



SCIENCE. 



[Vol. XX. No. 517 



-would be of advantage by the hold ihey would give to the squirm- 

 ing body. Then elongation would increase the advantage. No 

 loss of this function wo:ild be npcessary, but a gain, if the limb 

 acquired some independent motion, and this might be developed 

 enough to render it capable of officiating as the sole locomotive 

 organ. If such a history of the limb were true, the salamander 

 is midway in the line of descent. 



3. The post-anal region of the salamander is piscine, while the 

 anterior portions of the body are not, but are distinctly higher. 

 This fact is more or less familiar in a general wav and called by 

 Professor Hyatt, who pointed it out many years ago, by the name 

 " cephalizatioD." This advance of the anterior part of the body 

 of the salamander has left the " tail '" to be in many respects not 

 amphibian so much as piscine. Of course the term tail here 

 means post-anal region of the body and the portion, roughly 

 speaking, homologous with the post-anal region of the iish. In 

 the higher fishes this region has acquired a "tall,'' while the 

 ampbihia have not shared the acquisition of a structure sup- 

 ported by five rays, which does not belong to the ancient verte- 

 brate stcck. In this sense the tail of the salamander and its cor- 

 relate, the post anal region of the fish, are not only similar in 

 function, being organs of locomotion, but they are comparable 

 in their anatomy. The back-bone is acentrum with lii-concave 

 surfaces with tw:) equally developed arches, a neural arch con- 

 taining the spinal cord, and an haemal arch containing a vein and 

 an artery with oblique intervertebral muscles forming the back 

 of the organ. In vertebrates above the urodela, with the loss of 

 its locomotor function and the development of arms and legs, the 

 post-anal region becomes of less and less importance, though not 

 always disappearing; thus in many lizards it is large at its origin, 

 as large as the body befote it, and it has the peculiar power of 

 autotoiiy. as it has been called; that is, of breaking off in the 

 hands of a captor, whereby the animal escapes capture. There 

 is a gradual degeneration of the region among the higher verte- 

 brates, with many varieties of direction and degree of develop- 

 ment and occasional utilities in peculiar directions, and the sala- 

 mander stands at the bottom of this series. 



4. The death of the salamander is accompanied by a loss of 

 powers of movement, which is first manifest in the last acquired 

 (phylogenetically) of the powers, i.e., in the limbs, and finally in 

 the vertebree muscles. In specimens killed under the influence of 

 chloroform, after all movement had ceased in the limbs, the sin- 

 uations of ihe back-bone continued for some time, and were the 

 last raove'jients observed to take place. 



REFLEX ACTION IN TURTLES. 



By M. .T ELROD, ILLINOIS WESLEYAN UNIVERSITY, BLOOMINGTON, ILL. 



Recently I had a number of map turtles (Malacleniys geo- 

 graphicus Le Sueur) for student work, and observed, what is to 

 me, a remarkable instance of reflex muscular action, both in the 

 head and limbs. In one specimen the head had been severed 

 from the body fully an hour, when I observed the students 

 amusing themselves by tapping the nose of the severed head, 

 when almost as quickly as in life the jaws would open, and when 

 a pencil or other hard object was thrust in would close upon it 

 with seemingly as much viciousness as in life, continuing to hold 

 for some time, gradually relaxing, when the experiment would 

 be tried over again. This was the case not only with the one in 

 question, but with a half-dozen others of the same lot. Taking a 

 specimen with the head cut off and all the viscera cleared away, 

 leaving the legs attached to the carapace, the legs manifested 

 sensitiveness to a marked degree. In one specimen the four legs 

 extended from the body almost straight; a very gentle touch 

 with the point of a pencil on the tip of a claw caused that leg to 

 be drawn within the shell, so to speak, as quickly as in life. This 

 was done alternately with each foot to the first again, all giving 

 the same results. Several other specimens tested showed as much 

 and as sudden movement, and one killed at 3 p.m, , when touched 

 at It A M. the day following, withdrew its feet instantly. While 

 these observations are common for turtles, I have not observed 

 such marked results in other species. 



A LABORATORY OF PLANT DISEASES. 



BY C. W. WOODWOBTH, BEEKELKY, CAL. 



There has recently been equipped at the University of Cali- 

 fornia a laboratory for the study of the subject of plant diseases- 

 in its broadest sense ; and, as there are but few if any others 

 where the whole subject is taught as a unit, it may be well to 

 give an outline of the equipment for this class of work. 



We will not consider that part of the equipment for this work 

 afforded by the grounds, orchard, nursery, gardens, and green- 

 houses of the agricultural department, but confine ourselves to 

 the laboratory proper. The subject of plant diseases is now, and 

 will continue to be, associated with that of entomology, so that 

 the same equipment, to a considerable extent, serves for the two 

 subjects. 



The laboratory-room is something over twenty by thirty feet, 

 and is situate.i on the north side of the Experiment Station build- 

 ing. It is lighted by four windows, having an entirely unob- 

 structed view, and so giving ample light for microscope work. A 

 corner of the room is partitioned off for a private laboratory, and 

 a closet is fitted with a ruby window, affording an opportunity 

 for photo and blue-print work. The figure below will give aj 

 good idea of the arrangement of the room. 



tun. 



^'\x xss\s\\s^y.^;s' 



yv^^vv.\^vfj g ;;:?;^;^ 



The windows are all fitted with heavy shades working in 

 grooves, enabling one to darken the room very easily and quickly 

 when the lantern is to be used for illustration. The views are 

 projected on a screen of tracing-cloth, which is mounted on an 

 ordinary spring-roller and is ordinarily rolled up out of the way. 



Besides the benches near the windows, which are used by ad- 

 vanced students, there are also three long desks, one and a half 

 feet wide by twelve in length, that have proven themselves so 

 convenient that a sketch of one is presented. As can be seen on 

 the plan, ihese are so constructed that at the side of each student 

 boxes, the size of those of the collection, may be used as drawere, 

 or boards may be inserted forming shelves. 



Ctlass. 



GUjed Pa/iei'. 



Cork, 



■B'tderi .Saard. 



2 



The boxes used for the collection are made as shown in the aa- 

 companying figure, and are from their peculiar construction not 

 liable to warp or crack, and so remain perfectly insect- proof. 



