REGULAR FOUR-DIMENSIONAL HYPERSOLIDS. 21 



(^/3)„„. (>/),,,V (^^)<:,,' (^^)' (-^'^)' (^^)n:.' 



{Coc), (qS), (CcJ)^^^^^, (/Jc^), (/;/3), {By). 



The following lines are all bisected 



{Ib) {yè)^,^,^, {/C) {(2\^,{/j}) (^V)„„> 



(JB) (yê\^,^, {AC) {(2ê\^^^^, {/D) {(2y\,^_, . 



{B'C){uè), {B'D) {ay), {(/B) {uI2), 

 {B'C){cif), {B'l)){ay\ {C^I)){a^\ 

 {AB) {yè)^_^^^,{AC) (/3'<5)^^^^, {JI)) {0y)^^^^, 



{AB") {yf)^^^^, {AC-) {(2ê\, {AIJ) {(2y\^^, ■ 



{ B C') { aê) , { Bif) { uy) , { Clf) { a(è), 

 {BC) { ocf), {BU) {or/), { Clf) { a(i')- 



(6 February 1900). 



