The debate surrounding the government shutdown has been white hot in the Senate over the past few weeks, leading some lawmakers to complain about a lack of decorum.

Indeed, twice over the past two days, senators reminded their colleagues of Senate rules.

“I think we’ve all here in the Senate kind of lost the aura of Robert Byrd, who was such a stickler for Senate procedure,” Senate Majority Leader Harry Reid said Friday morning on the Senate floor. “I think we’ve all let things get away from us a little bit. The Senate is a very special place with very particular rules.”

Longstanding Senate precedents tied to the Senate’s original rules require senators to speak through the presiding officer, as noted in “Riddick’s Senate Procedure.”

“Senators in debate should address each other through the Chair and in the third person,” the book of precedents explains.

Additionally, Senate Rule 19 states: “No Senator in debate shall, directly or indirectly, by any form of words impute to another Senator or to other Senators any conduct or motive unworthy or unbecoming a Senator.”

Interestingly, Reid may have been reminding himself of those rules and precedents. The Nevada Democrat, who has sparred with tea party darling Sen. Ted Cruz over the past month, criticized the Texas Republican on Thursday for influencing  House Republicans’ political strategy.

“The latest plan came from the junior senator from Texas [and it] is to cherry pick parts of the government he likes,” Reid said. He added that House Majority Leader Eric Cantor, R-Va., “is following Cruz’s idea specifically. Sen. Cruz is now joint speaker. He lectures the House on occasion, as he does people over here.

Reid’s reference quickly drew criticism, particularly because Cruz was not on the floor at the time to defend himself.

“With all due respect to my good friend, the majority leader, he was speaking about the junior senator from Texas, who I don’t see on the floor here at the moment,” Senate Minority Leader Mitch McConnell, R-Ky., said. “The person to whom the speech seemed to be directed, I don’t see on the floor at the moment.”

Minority Whip John Cornyn of Texas followed McConnell by pointing out Rule 19.

Reid responded to these criticisms Friday.

“The practice that we observe is that when senators speak, they address themselves only to the presiding officer,” Reid said. “When senators — and this is something we all have to listen to — whether those other senators are in the chamber or not, senators must address and refer to each other in the third person and through the chair. … Senators should avoid using other senators’ first names and senators should avoid addressing other senators directly as ‘you.’ These rules are a little unusual, but they’ve been in place for a couple centuries.”

Despite these remarks, senators again were reminded of the rules and precedents while arguing over whether to approve a House-passed bill to fund parts of the government, including veterans programs and the National Institutes of Health.

“It is clear from the actions of the House and his actions today that he is starting to try to reconcile in his mind all the damage this government shutdown, which he inspired, is causing across the United States,” Majority Whip Richard J. Durbin said of Cruz. “What the junior senator from Texas is doing is picking and choosing those he will allow in the life boat. I understand the anxiety you feel about the problems you have created, but trying to solve them one piece at a time is not the American way. … I would say to my colleague from Texas, some of the language which he has used in this debate relative to impugning the motives of other members may have crossed the line.”

Cruz later shot back at Democrats who have been invoking his name on the Senate floor: “I am quite grateful for the majority leader admonition this morning toward civility on the floor. … It has been several days since I have been on the floor of the Senate but yet I feel I have been here in absentia because so many Democrats have invoked my name as the root of all evil in the world and the same majority leader that gave an ode to civility just a few days ago was describing me and anyone who might agree … as — quote — ‘anarchists.'”

After the exchange, the presiding officer, Democratic Sen. Christopher S. Murphy of Connecticut, offered “for the edification of all senators” the language of Rule 19.

Niels Lesniewski contributed to this report.