Wilder.] 540 j-j^ly 15^ 



the series, is called the fourth ventricle. The more or less distinct cavities 

 corresponding to the cerebellum and the Lobi optici are not called ventricles 

 at all, and the third is between the thalami. The two "lateral" A^entricles 

 are rarely mentioned as the first and second, but since the numbers must 

 be understood in order to account for the third and fourth, the student 

 desires, in vain, to know which is the first and which the second. In point 

 of fact, if the enumeration is begun at the cephalic end of the series, the 

 lateral ventricles are the third and fourth, since there are well-developed 

 ventricles in the LoM olfactorii. Finally, a "_/i/^A ventricle " is mentioned, 

 which is not only at the greatest distance from the fourth, but has no 

 normal connection with the other ventricles, and is, in fact, no part of the 

 series. 



In view of all this, the task of describing to students the highways and 

 by-ways of the brain — which should be most attractive because therein is 

 most clearly manifested the ideal arrangement of the organ — is one from 

 which I shrink as from any other kind ot solemn nonsense. To my mind, 

 indeed, rather than go on as we have been going, it would be at once more 

 philosophical and more intelligible to adopt the simple vocal device em- 

 ployed by Straus-Durckheim for the designation of the Ossa metatarsalia — 

 "padion, pediou, pidion, podion, pudion" — and to re-christen the ventricles 

 by, for instance, the names pran, pren, prin, pron, and prun. 



Fortunately, however, another alternative is presented. Assuming that 

 the terms rhinencephalon, prosencephalon, diencephcdon, onesencephalon, 

 epencephalon and metencephalon are to be retained, and that they are to 

 be learned by successive generations of students, why should we not 

 transfer the distinctive prefixes to the Greek word for ventricle, zoj/j'a, 

 cceliaf This would give us rhinoccdia, procmlia, diaccdia, mesoccelia, epicoeUa, 

 and metaccdia. 



These terms are capable of inflection, and the longest of them is no 

 longer than the Latin ventriculus, which requires a prefix or qualifying 

 word. These prefixes may be also employed for the designation of the 

 membraneous roofs of the "third" and "fourth" ventricles, and the 

 plexuses of these and the lateral ventricles. Thus we should have meta- 

 tela and metaplexus, diatela, and diaplexus, proplexus, portiplexus, and auU- 

 plexus. Two or more "ventricles" would be spoken of as cteZto?, while 

 the "fifth ventricle," which is really no part of the series, may well 

 be called pseudoca>lia. 



Aula. — I hope, before long, to justifj^ more fully the proposition already 

 made (Wilder, 5 and 5), to consider the cephalic portion of the "third ven- 

 tricle" between the porto (Foramina Monroi), as a morphologically inde- 

 pendent cavity under the name of aula. 



Porta. — This is proposed as a convenient substitute for the phrase 

 "Foramen Monroi." If the two orifices leading, respectively, from the 

 two proccBlise ("lateral ventricles"), into the aula, and so communicating 

 with the entire mesal series of coelise, were seldom employed, or even as 

 frequently as "Foramen Magendie, " there might be less call for a change 

 of name ; but, according to my view of the best method of studying the 



